HairFactz Definitions
Some words have more than one meaning. Only those meanings relating to this site will be used.
Albino
Having pale or colorless hair, eyes, and skin because the body does not produce enough pigment. (Pigment is the dyelike material in cells that provides color). More about Albinism.
Alopecia
Pronounced - al-oh-PEE-shuh
The lack of or loss of hair from areas of the body where hair is usually found. Alopecia can be a side effect of some cancer treatments.
Alopecia Areata
Pronounced - al-oh-PEE-shuh ar-ee-AH-tah
An autoimmune, often reversible disease in which loss of hair occurs in sharply defined areas usually involving the scalp or beard, but at times every hair on the body. More about Alopecia Areata.
Alopecia Areata Totalis
A form of alopecia areata characterized by the total loss of hair from the scalp and face.
Alopecia Areata Universalis
A form of alopecia areata in which all hair on the scalp, face, and body is lost.
Amorphous
Without definite form, shape, pattern, or character.
Anagen
The anagen phase of the hair growth cycle is when a hair root actively grows. At any given time approximately 80 to 90 percent of our hair is in the anagen phase. The anagen phase lasts approximately 2 to 7 years but may vary from a few months to about 10 years. The root from a pulled anagen hair is elongated, may be covered with a root sheath (protective surrounding), and is usually fully pigmented (colored).
Androgen
Hormones that stimulate sebaceous glands in addition to other effects on the body. Present in both males and females, androgens are responsible for physical maturation in males and therefore occur in much higher levels in males. Males tend to have more severe acne than females. Levels of androgen that are higher than normal can lead to excessive hair growth, acne, weight gain, and problems with ovulation in females.
Baldness
Baldness is partial or complete hair loss in both men and women. Also called alopecia. More about Baldness.
Barber's Itch
A staph infection of the hair follicles in the beard area of the face, usually the upper lip. Shaving aggravates the condition. More about Barber's Itch.
Bleaching
A chemical or a natural process used to make a hair colorless or lighter than its usual color. Artificial bleaching removes pigment (color) from the hair and can give the hair a characteristic yellow cast. Harsh or repeated treatments can make the hair shaft brittle.
Buckling
An abrupt change in the shape and orientation of a hair shaft with or without a slight twist, often seen in pubic hairs.
Cartilage Hair Hypoplasis
A hair disorder that results in abnormally fine, sparse, and lightly colored hair that is usually short.
Catagen
The catagen phase of the hair growth cycle is when hair growth begins to shut down and stop activity. Approximately 2 percent of our hair is in the catagen phase at any given time. Catagen phase is the transitional phase from the active growth phase (anagen) to the resting growth phase (telogen) in the hair growth cycle.
Cessation
To cease, stop, or pause.
Chronic
Pronounced - KRAW-nik
A term that refers to disorders that last a long time, often years. A chronic condition is one lasting 3 months or more, by the definition of the U.S. National Center for Health Statistics.
Color
Color is the aspect of objects that may be described in terms of hue, lightness, and saturation. It should be recognized that the macroscopical and microscopical colors of hairs might appear different. Macroscopic is a term that describes characteristics large enough to be perceived without magnification. Microscopic is a term that describes characteristics too small to be resolved by the unaided eye but large enough to be resolved with the microscope.
Compulsive Hair Pulling
Compulsive hair pulling, called trichotillomania, pronounced - trik-o-til-o-MAY-ne-uh, is a chronic (lasting a long time) psychiatric (pertaining to mental illness) condition characterised by uncontrollable, self-inflicted, hair pulling or twisting and twirling of the hair until it breaks off, resulting in noticeable hair loss. More about Compulsive Hair Pulling.
Congenital
A condition, disease, or disorder that is congenital is one that is present at birth.
Convolution
An abrupt rotation of the hair shaft that can occur naturally, from disease, or as a result of mechanical force.
Cornea
The cornea is the clear, front part of the eye. The cornea is the first part of the eye that bends (or refracts) the light and provides most of the focusing power.
Photo of eye anatomy showing the cornea.
Cortex
The middle portion of a hair between the cuticle (outer layer of the hair) and the medulla (core of the hair) composed of elongated and fusiform (spindle-shaped) cells. It may contain pigment granules, cortical fusi (air spaces ), and/or large oval-to-round-shaped structures called ovoid bodies.
Cortical Fusi
Air spaces located in the cortex of hairs. They are commonly found near the root of a mature human hair, although they may be present throughout the length of the hair.
Corticosteroids
Potent anti-inflammatory hormones that are made naturally in the body or synthetically (man made) for use as drugs. They are also called glucocorticoids. The most commonly prescribed drug of this type is prednisone.
Cradle Cap
Cradle cap is the term used when seborrheic dermatitis affects the scalp of infants. Seborrheic dermatitis is a common, inflammatory skin condition that causes flaky, white to yellowish scales to form on oily areas such as the scalp or inside the ear. It can occur with or without reddened skin. More about Cradle Cap.
Curled
A hair shaft form that is bent into or towards a spiral form.
Curved
A hair shaft form with slight curvature but does not exhibit waviness or does not curl back upon itself to form a circle.
Cuticle
The outer layer of a hair composed of layers of overlapping scales.
Dandruff
Dandruff is a common condition involving an increased rate of shedding of dead epidermal (outer layer of the skin) cells of the scalp that causes flaky, white to grayish scales to form, and is usually accompanied by itching.
Depilatory
Pronounced - di-pil-uh-tor-ee
Depilatory products remove unwanted hair at the skin's surface. Available in gels, creams, lotions, aerosols, and roll ons. Apply it, wait, wash or wipe it off. Depilatory products are not a permanent hair removal method. Results last approximately a week. More about Depilatories.
Dermal Papilla
Connective living tissue from which hair is generated from the follicle in the thick layer of the skin below the epidermis. Skin is made up of three layers:
- First layer of skin - Epidermis - the tough, protective, topmost outer layer that covers the body
- Second layer of skin - Dermis - the middle layer, under the epidermis, also called corium or derma
- Third layer of skin - Subcutis or Hypodermis - fatty layer of subcutaneous tissue, the bottom, deepest layer
Distal End
The end of the hair away from the root, towards the tip.
DNA
DNA stands for deoxyribonucleic acid, the chemical substance from which genes are made. DNA is a long macromolecule that carries a person's genetic information. DNA is a double-stranded molecule held together by weak bonds between base pairs of nucleotides. The four nucleotides in DNA contain the bases adenine (A), guanine (G), cytosine (C), and thymine (T). In nature, base pairs form only between A and T and between G and C; thus the base sequence of each single strand can be deduced from that of its partner.
Dye
A chemical used to artificially color hair.
Electrolysis
Pronounced - uh-lik-tral-i-sis
In electrolysis, an electrical current is used to remove unwanted hair. Medical electrolysis devices destroy hair growth with a shortwave radio frequency after a thin probe is placed in the hair follicle. Risks from these methods include infection from an unsterile needle and scarring from improper technique. More about Electrolysis.
Elongate
Longer in length than in width, stretched, extended, drawn out.
Epilators
Two types of devices use electric current to remove hair: The Needle Epilator and the Tweezers Epilator. Epilators remove hair at the root. More about Epilators
Eumelanin
The black and brown pigment occurring in human and animal hair.
Follicle
Pronounced - fol-ih-kul
The tiny cavity or opening in the skin through which a hair grows (the root of an individual hair), and sebum is excreted from sebaceous glands to the surface of the skin.
Follicular Tag
Tissue from a hair follicle that is still attached to the root end of a hair.
Folliculitis
Folliculitis is an infection of a hair follicle. Folliculitis can occur anywhere on the body where there is hair, although it is mostly common on the face, scalp, and areas rubbed by clothing, such as the thighs and groin.
Fungal Tunnels
Air pockets in a hair shaft caused by fungal (relating to fungus or fungi) growth.
Fur Hairs
Fine hairs that make up the undercoat of mammals and provide warmth.
Fusiform
Fusiform is a term that refers to a spindle-shaped (tapered at each end) gap present in the hair shaft.
Genes
Pronounced - jeans
Genes come from both parents and are responsible for inherited characteristics, such as eye and hair color. Genes are in all body cells.
Gray Hair
Scientists continue to investigate why hair turns gray. Gray hair results from a reduction of pigment, while white hair has no pigment. In time, everyone's hair turns gray.
Guard Hairs
Coarse hairs that provide protection and are usually longer than fur hairs.
Hair
One of the numerous, fine, threadlike structures that grow from the skin of humans or animals. Hair is made up of dead cells filled with proteins, most of which are known as keratins. Hair is dead tissue. Once hair is damaged it cannot be repaired, except by re-growth. The only "living part of a hair" is the root, called a follicle, a tiny cavity or opening in the skin through which a hair grows.
Hair Cuticular Cast
A freely movable, firm yellowish-white material ensheathing scalp hairs resulting from scalp disorders such as psoriasis or seborrhoeic dermatitis.
Hair Follicle
Pronounced - hair fol-ih-kul
A tiny cavity or opening on the surface of the skin through which a hair grows.
- Alopecia - pronounced al-oh-PEE-shuh, lack of or loss of hair from areas of the body where hair is normally found.
- Alopecia Areata - pronounced al-oh-PEE-shuh ar-ee-AH-tah, is an autoimmune, often reversible disease in which loss of hair occurs in sharply defined areas usually involving the scalp or beard, but at times every hair on the body.
- Alopecia Areata Totalis - total loss of hair from the scalp and face.
- Alopecia Areata Universalis - hair loss from the entire body, including the eyebrows, eyelashes, and body hair.
Hair Peripilar Cast
Hair peripilar cast is a freely movable, firm, yellowish-white material ensheathing scalp hairs resulting from scalp disorders, such as psoriasis or seborrhoeic dermatitis.
Heredity
The transmission of characteristics from one generation to the next.
Hirsute
Hairy; Covered with hair.
Hirsutism
Pronounced - HER-suh-tiz-um
Increased hair growth on the face, chest, stomach, back, thumbs, or toes.
Hyperpigmented
Darker skin color than the surrounding skin.
Hyperthyroidism (overactive thyroid)
Pronounced - HY-per-THY-ROY-dih-zum
When too much thyroid hormone is made, it is called overactive thyroid or hyperthyroidism. Symptoms include weight loss, chest pain, cramps, diarrhea, and nervousness.
Hypothyroidism (underactive thyroid)
Pronounced - HY-poh-THY-ROY-dih-zum
When not enough thyroid hormone is made, it is called underactive thyroid or hypothyroidism. Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold.
Hypertrichosis
Excessive growth of hair on the body.
Hypotrichosis
Less than the normal amount of hair on the scalp and body.
Imbricate
A term that describes a scale pattern with edges overlapping in a wavy pattern. This pattern is typical of human hair.
Inflammation
Redness, swelling, and pain.
Inherit
In genetics (genetics is the study of inheritance patterns of specific traits), to receive genetic material from your parents through biological processes.
There are no entries for the letter J.
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Keloid
Pronounced - KEY-loyd
A keloid is an overgrowth of scar tissue at the site of a healed skin injury. Also called hypertrophic scar or keloid scar.
Keratin
Keratin is an extremely tough protein substance found in hair, finger nails, skin, and cornea of humans, and feathers, horns, and hooves of animals.
Keratinocytes
Cells that synthesize keratin and are found in the skin, hair, and nails. A fibrous protein is produced by keratinocytes and may be hard or soft. The hard keratin is found in hair and nails. The soft keratin is found in the epidermis (protective outer layer) of the skin in the form of flattened non-nucleated scales that slough continually.
Kinked
Hair that is closely curled or twisted.
Lanugo
Fine hairs found on newborn babies, and lost shortly after birth.
Lice
Lice are parasitic insects that may be found on humans. These include head lice, body or clothing lice, and crab lice that live in the pubic region, eyelashes, or eyebrows. More about Lice Aren't Nice!.
Mammal
Warm blooded animals, including humans, with a backbone (vertebrate). Usually have some hair or fur, and most females give birth and nourish their young by milk producing mammary (breast) glands. Includes more than 4,000 species.
Medial Region
The portion of the hair between the proximal end (portion of the hair towards the root) and distal end (end of the hair away from the root, towards the tip).
Medulla
The central portion of hair, the core area.
Melanin
Melanin is responsible for skin and hair pigmentation (color). Two forms of melanin, eumelanin and phaeomelanin, determine the color of human hair and animal hair.
Monilethrix
Monilethrix is a hair disorder that results in periodic nodes or beading along the length of the hair with intervening, tapering constrictions that are not medullated.
Morphology (Adjective - Morphological)
Shape, form, external structure, or arrangement, especially as an object of study or classification.
Nits
Nits are lice (plural of louse) eggs. When a female louse finds its way onto the head of a person, she starts laying eggs (nits) along with a glue that firmly attaches the nits to the hair close to the scalp. More about Lice Aren't Nice!.
Opaque
Not transparent or translucent, cannot see through it, like an obscure (not clear) window letting little light pass through it, having no luster, dull.
Origin
The beginning of existence of something.
Ovoid Bodies
Oval-shaped, heavily pigmented bodies that may occur in the hair cortex.
Papilla
Connective tissue from which hair is generated from the follicle.
Papules
An inflammatory comedo (comedo: an acne lesion) that resembles a small, red bump on the skin.
Pathogenesis
The origin and development of any disease condition.
Peripheral Region
The portion of the hair toward the outermost areas of the hair, distant from the medullary or central region, including the cuticle and the outer areas of the cortex.
Phaeomelanin
A reddish brown to yellow pigment occurring in human and animal hair.
Pigment
Pigment is the dyelike material in cells that provides color to skin, eyes, and hair.
Pigment Granules
Melanin granules whose size, shape, density, and distribution vary.
Pigmentation
Coloration or discoloration resulting from pigment.
Pili Annulati
Pili annulati is a hair disorder that results in ringed or banded hair, alternating bright and dark bands in the hair shaft. The dark bands are a manifestation of the abnormal air spaces in the cortex.
Pili Bifurcati
Pili bifurcati is a genetic hair disorder characterized by two hairs joined at the shaft along their entire length.
Pili Torti
Pili torti is a genetic hair disorder characterized by the hair shaft being flattened and twisted 180 degrees numerous times along its axis. It is usually found at irregular intervals along the shaft.
Polycystic Ovary Syndrome (PCOS)
PCOS is a mild hormonal imbalance that can cause irregular periods, unwanted hair growth, weight gain, and acne. This is a common condition that begins during the teenage years. More about Polycystic Ovary Syndrome (PCOS).
Postmortem Banding
(Postmortem means occurring after death). Postmortem banding is the appearance of an opaque microscopic band near the root area of hairs from a decomposing (rotting or decaying) body. When hairs originate from a body in a state of decomposition, a dark band may appear near the root of the hair. This characteristic has been labeled a postmortem root band.
Photo is a postmortem root band.
Proximal End
The portion of the hair towards the root.
Pruritic
Itchy. Pruritic is an adjective to Pruritus.
Pustules
Acne pustules are small, white, pus-filled, blister-like lesions on the surface of the skin and are red at the base with surrounding inflammation.
Putrid Root
Putrid root is a tapered or brush-like appearance of the proximal end (the portion of the hair towards the root) caused by decomposition (the process of decay).
There are no entries for the letter Q.
Razor Cut Hair
A razor cut hair is angular and very straight or clean.
Photo is a hair cut with a razor.
Root
The root is the structure at the proximal end of a hair. The mature hair root will be hardened, have a bulbous shape (shaped like a bulb), and have little or no follicular tissue adhering to it. Pigment is sparse or absent, and there is frequently an abundance of cortical fusi. A root that has been plucked prior to maturation will be soft, have a distorted appearance, and may have tissue adhering to it. Pigment is present, and there are rarely cortical fusi. A catagen root may exhibit the bulbous shape with a tag attached. Hairs are naturally sloughed from the body after a period of growth. The life cycle of hair includes:
- Anagen phase - when a hair root is actively grows.
- Catagen phase - when hair growth begins to shut down and stop activity. Catagen phase is a transitional root stage between the anagen (actively growing) phase and telogen (resting) phase.
- Telogen phase - the last phase of the hair growth cycle when a hair is resting and is ready to be naturally shed. After the telogen phase, the hair growth process starts over again to the anagen phase.
Seborrheic Dermatitis
Seborrheic dermatitis is a common, inflammatory skin condition of the scalp or body characterized by irritation, itching, redness, and excess shedding of dead epidermal (outer layer of the skin) cells. Seborrheic dermatitis is a chronic (life-long) condition that can be controlled with treatment. It often has extended inactive periods followed by flare-ups.
Scissor Cut Hair
Cutting hair with scissors produces a sheared or square cut end.
Photo is a hair cut with a scissors.
Shaft
The portion of a hair between the root and the tip.
Splitting
Splitting is damage usually occurring at the distal end of a hair when the hair divides down the long axis. Distal end is the end of the hair away from the root, towards the tip.
Photo is a split hair.
Sugaring
Sugaring hair removal is similar to waxing hair removal. A heated sugar mixture is spread on the skin, sometimes covered with a strip of fabric, and then lifted off to remove hair.
Systemic
Pronounced - sis-TEH-mik
Affecting the whole body.
Tactile Hairs (Vibrissae)
Whiskers only found on animals.
Telogen
Telogen is the last phase of the hair growth cycle when a hair is resting and is ready to be naturally shed. The hair root becomes a bulbous (shaped like a bulb) shaped root. It is the resting phase for hairs on the scalp, usually lasting 3 weeks to 3 months, and the resting phase is much longer for hairs on the eyebrow, eyelash, arm and leg. Approximately 10 to 18 percent of our hair is in the telogen phase at any given time. It is normal to lose some telogen hairs each day. After the telogen phase, the hair growth process starts over again to the anagen phase.
Terminal Hair
Developed hair, which is long, coarse, generally pigmented hair (darker in color), and can be found on the scalp, armpits, pubic area and in males the beard area, chest, legs, and back.
Texture
The appearance and feel of hair due to its length, thickness, and shaft form.
Tip
The most distal end of a hair shaft. (Distal end is the end of the hair away from the root, towards the tip. The shaft is the portion of a hair between the root and the tip).
Threading
Threading hair removal is an ancient technique in which a loop of thread is rotated across the skin to pluck the hair. May cause skin irritation and infection.
Trichologist
A doctor who specializes in the study of the structure, functions, and diseases of the hair.
Trichology
The study of the structure, functions, and diseases of the hair.
Trichonodosis
Trichonodosis is a condition characterized by apparent or actual knotting of the hair.
Trichoptilosis
Trichoptilosis is a disease condition characterized by longitudinal splitting or fraying of the hair shaft.
Trichorrhexis Invaginati
Trichorrhexis invaginati is a genetic disease characterized by a segment of bulbous, dilated hair enfolded into a concave hair terminal, recalling the appearance of a bamboo node. If the hair breaks at the bulbous end, the hair has a "golf tee cup" end.
Trichorrhexis Nodosa
Trichorrhexis nodosa is a condition characterized by the formation of nodes, and in extreme cases, the hair is weaker at the node and is subject to breakage.
Trichoschisis
Trichoschisis is a condition characterized by brittle hair with a transverse crack or a clean break.
Undulate
Changes in the true diameter along the length of the hair shaft that results in change in the cross-sectional shape. This can give the hair a wavy appearance.
Vellus
Vellus is fine body hair.
Waardenburg Syndrome
Waardenburg Syndrome (WS) is a hereditary disorder that is characterized by hearing impairment, distinctive hair coloring such as a patch of white hair or premature gray hair as early as age 12, and/or distinctive blue color to one or both eyes, and wide-set inner corners of the eyes. Balance problems are also associated with some types of Waardenburg syndrome. More about Waardenburg Syndrome.
Waved
A hair shaft form with curvature that changes its direction to produce a sinuous (curving in and out) wave form and does not curve back upon itself to form a circle.
Waxing
Waxing removes hair at the root. Waxing is not a permanent hair removal method. Results last about 3 to 8 weeks.
There are no entries for the letter X.
There are no entries for the letter Y.
Zinc
Zinc is an essential mineral that is found in almost every cell. It stimulates the activity of approximately 100 enzymes, which are substances that promote biochemical reactions in your body. Zinc supports a healthy immune system, is needed for wound healing, helps maintain your sense of taste and smell, and is needed for DNA synthesis. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence. Zinc deficiency most often occurs when zinc intake is inadequate or poorly absorbed, when there are increased losses of zinc from the body, or when the body's requirement for zinc increases. Signs of zinc deficiency include:
Hair loss - alopecia (hair loss) - a few studies that examined the efficacy of zinc in treating alopecia report conflicting results. Additional information is needed before a conclusion can be made.
Growth retardation.
Diarrhea.
Delayed sexual maturation and impotence.
Eye and skin lesions.
Loss of appetite.
There is also evidence that weight loss, delayed healing of wounds, taste abnormalities, and mental lethargy can occur. More about Zinc.