Bowfin \Bow"fin`\, n. (Zo["o]l.) A voracious ganoid fish ({Amia calva}) found in the fresh waters of the United States; the mudfish; -- called also {Johnny Grindle}, and {dogfish}. Grindle \Grin"dle\, n. (Zo["o]l.) The bowfin; -- called also {Johnny Grindle}. [Local, U. S.]