With small cycloid scales, clinoid blennies may have a deep or slender build; some members of the family bear the name "snake blenny" and "eel blenny" for this reason. Dorsal spines outnumber soft rays; there are two spines in the anal fin. Like many other blennies, clinids possess whisker-like structures on the head called cirri.
The majority of species possess rich, highly variable coloration in shades of reddish brown to olive, often with cryptic patterns; this suits the lifestyle of clinid blennies, which frequent areas of dense weed or kelp. Generally staying within intertidal zones to depths of about 40 metres, some species are also found in tide pools. Eggs are deposited on kelp for the male to guard. Clinids feed primarily on small crustaceans and mollusks.