stickleback

noun

Any of various small freshwater and marine fishes of the family Gasterosteidae, having erectile spines along the back.

noun

Any fish of the family Gasterosteidæ: so called from the sharp spines of the back.

noun

Any one of numerous species of small fishes of the genus Gasterosteus and allied genera. The back is armed with two or more sharp spines. They inhabit both salt and brackish water, and construct curious nests. Called also sticklebag, sharpling, and prickleback.

noun

Any one of numerous species of small fishes of the genus Gasterosteus and allied genera. The back is armed with two or more sharp spines. They inhabit both salt and brackish water, and construct curious nests.

noun

small (2-4 inches) pugnacious mostly scaleless spiny-backed fishes of northern fresh and littoral waters having elaborate courtship; subjects of much research