Smegma is a combination of shed skin cells, skin oils, and moisture. It occurs in both male and female mammalian genitalia. In females, it collects around the clitoris and in the folds of the labia minora; in males, smegma collects under the foreskin.

The labia minora, also known as the inner labia, inner lips, or nymphae, are two flaps of skin that are part of the primate vulva, extending outwards from the vaginal and urethral openings to encompass the vestibule. The labia minora are situated between the labia majora and together form the labia. They vary widely in size, color and shape from individual to individual.