Loco

LOCO – [Latin] to place; to let for hire

Merriam-Webster Online Dictionary
loco (adverb or adjective)
in the register as written - used as a direction in music
loco (noun)
1.
- locoweed
2.
- locoism
loco (verb)
transitive verb
1.
to poison with - locoweed
2.
to make frenzied or crazy
loco (adjective)
slang mentally disordered - crazy frenzied