Definitions for "loony"
Crazy; insane; lunatic; mentally unsound.
someone mentally deranged and possibly dangerous.
informal or slang terms for mentally irregular; "it used to drive my husband balmy"
Keywords:  impractical, foolish, ideas
Very foolish; very impractical; as, loony ideas.
Keywords:  luny, see
See Luny.
Affectionate term for the Canadian Dollar.