Glossary of Dermatologic Terms
Abscess – A closed pocket containing pus. Some abscesses are easily diagnosed clinically, as they are painful and may “come to a head” such that pus becomes visible, but deep and chronic abscesses may just look like a TUMOR clinically and require biopsy to distinguish them from neoplasm.
acne – a chronic disorder of the hair follicles and sebaceous glands. Acne is characterized by black heads, pimple outbreaks, cysts, infected abscesses, and (sometimes) scarring.
AK– (Actinic Keratosis)- Small, dry, scaling lesions occurring on sun-exposed areas of the skin.
albinism – a rare, inherited disorder characterized by a total or partial lack of melanin (skin pigment) in the skin.
alopecia – baldness.
angioma – a benign tumor in the skin, made up of blood or lymph vessels.
atopic dermatitis (Also called eczema.) – a skin disorder that is characterized by itching, scaling, thickening of the skin, and is usually located on the face, elbows, knees, and arms.
Atypical – The simple, straightforward definition would be “unusual,” but “atypical” means much more than that. In a diagnosis, the use of the term atypical is a vague warning to the physician that the pathologist is worried about something, but not worried enough to say that the patient has cancer.
Atypical nevus– a mole that may appear pink, white, or skin colored that has irregularities determined by a histological examination. These moles are classified as mild, moderate, or severe atypical. Removal is recommended for moderate and severe atypical nevi.
basal cell carcinoma – the most common form of skin cancer, characterized by small, shiny, raised bumps on the skin that are fragile and often bleed.
basal cells – these cells are found in the outer layer of skin. Basal cells are responsible for producing the squamous cells in the skin.
Biopsy– a technique utilized to help the clinician diagnose an existing lesion, rash, or other dermatological condition. During a biopsy the area selected is numbed with a local anesthetic and a small piece of the area to be analyzed is removed. Types of biopsies include, shave, punch, and excision.
birthmark – abnormality of the skin that is present at birth or shortly afterward.
blister – a fluid-filled bump.
boil – tender, swollen areas that form around hair follicles.
bullous – A large blister (a thin-walled sac filled with clear fluid).
candidiasis (Also called yeast infection.) – a skin infection caused by yeast that can occur in the skin folds, the navel, vagina, penis, mouth, and nail beds.
carbuncles – clusters of boils on the skin.
Carcinoma – A malignant NEOPLASM whose cells appear to be derived from EPITHELIUM. This word can be used by itself or as a suffix. Cancers composed of columnar epithelial cells are often called adenocarcinomas. Those of squamous cells are called squamous cell carcinomas.
cavernous hemangioma – a raised, red or purple mark in the skin, made up of enlarged blood vessels.
cellulitis – a bacterial infection of the skin that is characterized by swelling and tenderness.
chemical burns – burns due to strong acids or alkalines coming into contact with the skin and/or eyes.
chemical peels – a procedure often used to minimize sun-damaged skin, irregular pigment, and superficial scars. The top layer of skin is removed with a chemical application to the skin. By removing the top layer, the skin regenerates, often improving the skin’s appearance.
cold sore – recurrent, small blisters around and in the mouth caused by the herpes simplex virus.
collagen – a protein produced by skin cells that provide strength and resilience to the skin.
congenital – present at birth.
contact dermatitis – a rash or an inflammation of the skin caused by contact with various substances.
crust (Also called scab.) – a formation of dried blood, pus, or other skin fluid over a break in the skin.
Cryosurgery– the use of liquid nitrogen to destroy visible skin lesions. Commonly used for actinic keratoses, verruca vulgaris, and molluscum contagiosum.
cyst – a deep lesion that is filled with pus or other contents.
dermatitis – a number of skin conditions characterized by inflammation of the skin.
dermatofibroma – small, red or brown bumps in the skin.
dermis – the middle layer of skin, which is made up of blood vessels, lymph vessels, hair follicles, and sweat glands.
dermoid cyst – a benign tumor made up of hairs, sweat glands, and sebaceous glands.
eczema – a skin disorder that is characterized by itching, scaling, thickening of the skin, and is usually located on the face, elbows, knees, and arms.
ED&C– (electrodesiccation and curettage)- A technique used to treat certain types of superficial skin cancers. The area to be treated is injected with a local anesthetic. Curettes are used to destroy the lesion. A hyfrecator is then used to attain hemostasis.
electrical burns – burns due to contact with an electrical current.
EIC– (Epidermal Inclusion Cyst)- a small benign cyst in the epidermis caused by blocked pilosebaceous follicles. May be removed by surgical excision.
epidermis – the outer layer of skin, which is made up of the horny layer, squamous cells, and basal cells.
Epithelium – A specialized type of tissue that normally lines the surfaces and cavities of the body.
erythema nodosum – a skin condition, characterized by red bumps that usually appear on the shins.
erythrasma – a skin infection of the top layer of skin characterized by irregular pink patches that turn to brown scales.
Excision– involves the use of a local anesthetic and the removal of a skin lesion by use of a surgical scalpel. The excised area is then sent to a laboratory for pathologic evaluation.
Excisional biopsy– a surgical scalpel is used to excise a small portion of the tissue for analysis. Excisional biopsies are used for larger, deeper lesions. Sutures will be required for this type of biopsy.
exanthem – a rash.
excoriation – an area of the skin covered by a crust, or scab, usually caused by scratching.
Extraction– a method of removing unwanted skin lesions such as milia or comedones on the face. A small lancet is used to puncture the lesion. Then an instrument called a comedone extractor extracts the unwanted debris.
Fibrous Papule– a benign, small, firm, skin colored inflammation typically occuring on the nose of a middle aged person.
first-degree burns (Also called superficial burns.) – burns that only affect the epidermis, or outer layer of skin. The burn site appears red, painful, dry, and absent of blisters. Mild sunburn is an example. Scarring is usually rare or minimal.
folliculitis – an inflammation of the hair follicles due to an infection or irritation.
freckles – darkened, flat spots that typically appear only on sun-exposed areas of skin.
granuloma annulare – a chronic skin condition characterized by small, raised bumps that form a ring with a normal or sunken center.
Hemangioma– A benign tumor of dilated blood vessels.
herpes zoster (Also called shingles.) – a common viral infection of the nerves, characterized by a painful skin rash of small blisters anywhere on the body. It is a reactivation of chickenpox virus.
hives – see urticaria.
Hidradenitis Suppurativa – is a skin disease that most commonly affects areas bearing apocrine sweat glands or sebaceous glands, such as the underarms, breasts, inner thighs, groin and buttocks.
Hyfrecator– a small electrode that uses heat to destroy skin lesions and helps to stop bleeding.
immune system – a collection of cells and proteins that works to protect the body from potentially harmful, infectious microorganisms, such as bacteria, viruses, and fungi.
immunocompromised – an abnormal condition where one’s ability to fight infection is decreased. This can be due to a disease process, certain medications, or a condition present at birth.
impetigo – a bacterial skin infection characterized by microscopic pus-filled blisters.
inflammation – redness, swelling, heat, and pain in a tissue due to chemical or physical injury, infection, or allergic reaction.
Keloid– firm, elevated scar tissue that extends beyond the normal scar tissue.
keratinocytes (Also called squamous cells.) – these are the primary cell types found in the epidermis – the outer layer of skin.
keratosis pilaris – a common skin condition characterized by small, pointed bumps especially on the back and sides of the upper arms.
kerion – a large inflamed tender lesion that is a complication of ringworm of the scalp.
Lentigines– brown spots consisting of increased numbers of epidermal melanocytes.
lice – tiny parasites that can infest the skin; characterized by intense itching.
lichenification – skin that has thickened.
lipomas – round or oval lumps under the skin caused by fatty deposits.
lymphangioma – a raised, yellow-tan or red mark in the skin made up of enlarged lymphatic vessels.
macular stains (Also called angel’s kisses or stork bites.) – faint, red marks that appear in the skin at birth. Angel’s kisses are marks on the forehead and eyelids. Stork bites are marks on the back of the neck.
macule – the smaller version of a patch – a flat discolored spot.
malignant melanoma – a rare, but sometimes deadly, skin cancer that begins as a mole that turns cancerous.
melanocytes – cells present in the epidermis that produce melanin (skin pigment).
melasma – dark, brown, symmetrical patches of pigment on the face.
Milia– tiny, white, keratin filled cysts occurring on the face. May be treated by extraction.
moles – small skin marks caused by pigment-producing cells in the skin.
Mongolian spots – Bluish-black marks on the lower back and buttocks; affects mainly African-American or Asian children.
Monsel’s solution– Ferric subsulfate. Commonly used in the dermatology office to coagulate blood after biopsies.
Nevus– a discoloration of the skin due to pigmentation that is more commonly known as a mole. A nevus may be flat or raised. Benign nevi do not require treatment, however, changing nevi may be biopsied for evaluation.
nodule (Also called papule.) – a solid, raised bump.
paronychia – a skin infection around a finger or toenail.
patch – a flat, discolored spot.
Pathology– the interpretation of a specimen to determine the cause of the change in the skin. This is done by a clinician skilled in the analysis of skin using microscopic examinations.
pityriasis rosea – a common skin condition characterized by scaly, pink, and inflamed skin.
port-wine stains (Also called nevi flammeus.) – permanent flat, pink, red, or purple marks on the skin.
prickly heat – a rash caused by trapped sweat under the skin.
psoriasis – a chronic skin condition characterized by inflamed, red, raised areas that develop silvery scales.
Punch biopsy– utilizes a small device with a sharp circular edge to obtain a slightly deeper sample of tissue. Used to analyze tissue below the visible skin surface. A few sutures are required for this type of biopsy.
Purpura– condition of the skin characterized by hemorrhages. The skin may appear red, darkening to purple, then brownish-yellow and finally disappearing within a few weeks. Caused by various manifestations.
pustule (Also called pimple.) – inflamed lesions that look like pink bumps.
pyogenic granuloma – red, brown, or bluish-black raised marks caused by excessive growth of capillaries.
radiation burns -burns due to prolonged exposure to ultraviolet rays of the sun, or to other sources of radiation such as x-ray.
ringworm – a fungal skin infection characterized by ring-shaped, red, scaly, or blistery patches.
rosacea – a common facial skin condition characterized by redness, pimples, and broken blood vessels.
salicylic acid – a keratolytic drug (a drug that removes the outer layer of skin) that is used to treat various skin conditions.
scabies – an infestation of mites in the skin characterized by small pimples that itch.
scales – dead skin cells that look like flakes or dry skin.
scar – fibrous tissue that has formed after a skin injury.
Seb Derm– (Sebborheic Dermatitis) – inflammation of the scalp consisting of dry, scaling lesions. May also occur on the forehead nasolabial folds, eyebrows, or vermillion border of lips. Can be itchy, red, and greasy. Treated with topical creams and scalp solutions.
second-degree burns (Also called a partial thickness burn.) – burns that involves the epidermis and part of the dermis layer of skin. The burn site is red, blistered and painful, with possible swelling.
sebaceous glands – glands in the skin that secrete oil to the surface of the skin.
Sebaceous Hyperplasia– benign, elevated, soft, yellowish, raised bumps frequently found on the face.
SK (Sebborheic Keratosis)– A benign skin lesion occurring with the aging process. They appear on covered and uncovered areas of skin as raised rough spots. They may be light brown, brown or black. The color changes are harmless. These lesions do not need to be removed unless they itch, or become inflamed.
shave biopsy– a technique using a small flexible blade to shave the surface of the lesion for analysis. Typically used for superficial lesions of the skin.
skin Exam– A dermatology exam involves an assessment of the patient’s entire skin surface, hair and nails. During an examination any skin conditions found will be discussed with the patient to determine the proper treatment. A patient may return for evaluation of the treatment plan.
skin tags – soft, small, flesh-colored skin flaps on the neck, armpits, or groin.
spider angioma – a bright red mark with a distinct dark spot in the skin.
squamous cell carcinoma – a form of skin cancer that affects about 20 percent of patients with skin cancer. This highly treatable cancer is characterized by red, scaly skin that becomes an open sore.
squamous cells – see keratinocytes.
subcutis – the deepest layer of skin; consists of collagen and fat cells.
thermal burns – burns due to external heat sources which raise the temperature of the skin and tissues and cause tissue cell death or charring. Hot metals, scalding liquids, steam, and flames, when coming in contact with the skin, cause thermal burns.
third-degree burns (Also called a full thickness burn.) – burns that destroy the epidermis and dermis. The burn site appears white or charred black. There is no sensation in the area, because the nerve endings are destroyed.
thrush – a fungal infection of the mouth that usually causes a white coating on the tongue, cheeks or throat.
tinea versicolor – a common fungal skin infection characterized by white or light brown patches on the skin.
toxic epidermal necrolysis – a life-threatening skin disorder characterized by blistering and peeling of the top layer of skin.
tretinoin – a drug which is chemically related to vitamin A; used to treat acne and other scaly skin disorders.
urticaria (Also called hives.) – a condition in which red, itchy, and swollen areas appear on the skin – usually as an allergic reaction from eating certain foods or taking certain medications.
urushiol – resin in poison ivy plants that causes an allergic skin reaction.
vitiligo – smooth, white patches in the skin caused by the loss of pigment-producing cells.
wart – a noncancerous skin growth caused by a virus.