The
common name blenny (deriving from the
Greek and , mucus, slime) is ambiguous at best, as it has been applied to several families of
perciform marine, brackish, and some freshwater
fishes all sharing similar morphology and behaviour. Six families are considered "true blennies", all grouped together under the suborder
Blennioidei; its members are referred to as
blennioids. About 833 species are found in 130 genera within the suborder.