Silverfish, a small, wingless insect that is covered with tiny silvery scales. The body is slender and tapers toward the back part. The silverfish moves rapidly on three pairs of thin, jointed legs. Extending from its head is a pair of antennae and trailing from the rear of its body are three long, bristly appendages. The silverfish is about one-half inch (13 mm) long exclusive of the tail appendages.

Silverfish are common household pests. They live in dark, cool places, such as in basements, behind baseboards, and in closets. They are also often found around plumbing fixtures. Silverfish are usually unnoticed because they move about only in the dark. They feed on starchy materials and often damage clothes, books, and wallpaper. They can be controlled with insecticides.

The silverfish is Lepisma saccharina of the family Lepismatidae, order Thysanura.