| Adj. | 1. | loco - informal or slang terms for mentally irregular; "it used to drive my husband balmy"bats, batty, bonkers, buggy, crackers, daft, dotty, haywire, kookie, kooky, loony, loopy, nuts, around the bend, balmy, round the bend, wacky, whacky, barmy, nutty, fruity, cracked insane - afflicted with or characteristic of mental derangement; "was declared insane"; "insane laughter" | |