adj
loco
LOH-koh
adj
1
Crazy or out of one's mind (informal).
"He went completely loco when he heard the news."
"You'd be loco to turn down that offer."
noun
1
A poisonous rangeland plant (of the genus Astragalus or Oxytropis) that causes a form of madness in grazing animals when eaten.
"Cattle that graze on loco can start staggering and behaving erratically."
How to Use Loco
Learner’s notesIn plain EnglishCasual slang for "crazy" — also the name of a poisonous plant that sends grazing animals a bit mad.
When to use it
Informal; common in American English, often used half-jokingly.
Common pairings
go loco
drive someone loco
Word Forms
more loco comparative, locoed past tense, locos plural, locoes plural, locos singular, most loco superlative
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Etymology
Borrowed from Spanish loco, "crazy" or "mad."