Meaning

adjective of or characteristic of or resembling a lion

originThe adjective is derived from Late Middle English leonin, leonine (“of or pertaining to a person named Leo; specifically Pope Leo IV”), from Latin leōnīnus, from Leo (“man’s name”) (from leo (“lion”): see etymology 1) + -īnus (suffix meaning ‘of or pertaining to’). Etymology 2, adjective sense 2 (“being or relating to a kind of verse with internal rhyme”) is said to refer to a (possibly…

Etymology from Wiktionary, CC BY-SA 3.0