adverb
(music) A direction in written or printed music to be returning to the proper pitch after having played an octave higher or lower.
adjective
(colloquial) Crazy.
(Southwestern US) Intoxicated by eating locoweed.
noun
A certain species of Astragalus or Oxytropis, capable of causing locoism.
verb
(transitive) To poison with the loco plant; to affect with locoism.
(transitive, colloquial, by extension) To render insane.
noun
(rail transport, informal) A locomotive.