Fishel

Jewish (Ashkenazic): from the Yiddish personal name Fishl, literally ‘little fish’, used as a vernacular equivalent for the Biblical Efraym (Ephraim). Ephraim became associated with the fish because he was blessed by his father Jacob (Genesis 48:16) with the words veyidgu larov ‘Let them grow into a multitude’, the verb yidgu, containing the root letters of Hebrew dag ‘fish’.