naevus, nevus, nevo-, nev- +

(Latin: birthmark; mole)

Don't confuse this nevus with nurvus and even nervous (or "nerve"), which are quite different words and applications.

nevus araneus, spider nevus
Acquired or congenital dilation of the capillaries, marked by red lines radiating from a central red dot.
nevus comedonicus
A horny nevus that contains a hard plug of keratin (horn-like protein in the upper layer of the skin).

It is caused by failure of the pilosebaceous follicles (hair follicles and sebaceous glands) to develop normally.

nevus flammeus, port-wine stain
1. A large congenital vascular malformation nevus having a purplish color.

It is usually found on the head and neck and persists throughout life.

2. A large reddish-purple discoloration of the face or neck, usually not elevated above the skin.

It is considered a serious deformity due to its large size and color. In children, these have been treated with the flashlamp-pulsed tunable dye laser.

nevus sebaceus
Congenital papillary acanthosis of the epidermis, with hyperplasia of sebaceous glands developing at puberty and presence of apocrine glands in nonapocrine areas of the skin (commonly the scalp).

A variety of epithelial tumors may arise from a nevus sebaceus in adult life, most commonly basal cell carcinoma.

nevus spilus
A pigmented nevus with a smooth, unraised surface.
nevus unius lateris, linear epidermal nevus
A congenital systematized linear nevus limited to one side of the body or to portions of the limbs on one side.

Lesions are often extensive, forming wavelike bands on the trunk and spiraling streaks on the limbs.

nevus vascularis
A nevus in which superficial blood vessels are enlarged.

A nevus in which superficial blood vessels are enlarged. Nevi of this type are usually congenital.

They are of variable size and shape, slightly elevated, and red or purple in color. They generally appear on the face, head, neck, and arms, though no region is exempt. The nevi usually disappear spontaneously, but wrinkling, pigmentation, and scarring are sometimes seen.

nevus, naevus (s); nevi, naevi (pl)
1. A circumscribed malformation of the skin, especially if colored by hyperpigmentation or increased vascularity.

A nevus may be predominantly epidermal, adnexal, melanocytic, vascular, or mesodermal, or a compound overgrowth of these tissues.

2. Any lesion containing melanocytes; any birthmark; mole.
3. A congenital discoloration of a circumscribed area of the skin as a result of pigmentation.
4. A circumscribed vascular tumor of the skin, usually congenital, due to hyperplasia of the blood vessels.
5. A benign pigmented spot on the skin; such as, a mole (a cluster of melanocytes and supportive tissue that appears as a tan, brown, or flesh-colored spot on the skin).
6. A benign blood vessel tumor on the skin; such as, a vascular nevus, a local collection of capillaries of the skin (a strawberry birthmark, stork mark, or port wine stain).
7. Etymology: from the Latin naevus meaning "a body mole"; especially, "a birthmark".
subaceous nevus
An epidermal nevus containing sebaceous gland tissue.
verrucous nevus
A skin-colored or darker wartlike, often linear lesion appearing at birth or early in childhood and occurring in various sizes and locations, single or multiple.