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n. A stout-bodied killifish (Fundulus heteroclitus) of the Atlantic coast south of the Gulf of St. Lawrence, valued especially as bait.

n. A hardy killifish, Fundulus heteroclitus, found in brackish and coastal waters of the United States and Canada.

n. Any one of several species of small American cyprinodont fishes of the genus Fundulus, and of allied genera; the killifishes; -- called also minnow.

n. silver-and-black killifish of saltwater marshes along the Atlantic coast of the United States

"The most common of these have been the American eel, alewife, common mummichog, Atlantic silverside, and three sticklebacks (fourspine, threespine, and ninespine)."

killifish   

minnow    mummychog    mummachog