Entry 1 sense Webster, 1913 Grindle /grĭn'-dəl/ · Grin·dle · IPA /ɡrˈɪndəl/ 01 n. The bowfin; -- called also Johnny Grindle. 1. The bowfin; -- called also Johnny Grindle.(Zool.) [Local, U. S.] Also: Johnny Grindle