any of many species of tiny flying insects in the dipterid suborder Nematocera

A gnat [1] is any tiny fly in the suborder Nematocera.[2]

Gnat from Robert Hooke's Micrographia, 1665
A female black fungus gnat

"Gnat" is a loose descriptive category rather than a technical term. They can be both biting and non-biting. The biting ones are often called midges. Often they fly in large numbers, called clouds, in damp places like the Scottish Highlands.

One interesting group are the eye-gnats. the Smithsonian Institution describes them as “non-biting flies, no bigger than a few grains of salt, ... attracted to fluids secreted by your eyes”.[3]


  1. The G is not pronounced
  2. "Midges and Gnats | Entomology". Retrieved 2016-09-22.
  3. Gibbons, John. "Gnats always keep an eye out for a good place to eat". Smithsonian Institution. Retrieved 2018-01-21.