adj Uncommon

loco

LOH-koh

Loco (adj) means Crazy or out of one's mind (informal). Example: “He went completely loco when he heard the news.”

adj

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

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 notes

In 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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He went completely _____ when he heard the news.

Etymology

Borrowed from Spanish loco, "crazy" or "mad."

Origin: Spanish

Rhymes for loco

coco SoCo

See all rhymes for loco →

Frequently asked questions

What does “loco” mean?

The word “loco” means crazy or out of one's mind (informal). In plain terms, casual slang for "crazy" — also the name of a poisonous plant that sends grazing animals a bit mad.

How do you pronounce “loco”?

“Loco” is pronounced LOH-koh (/ˈləʊ.kəʊ/ in IPA).

How do you use “loco” in a sentence?

Here is “loco” used in a sentence: “He went completely loco when he heard the news.”

What part of speech is “loco”?

Depending on how it is used, “loco” can be an adjective and a noun.

Where does the word “loco” come from?

The word “loco” comes from Spanish. Borrowed from Spanish loco, "crazy" or "mad.".

Is “loco” a common word?

“Loco” is an uncommon word in modern English.

How many meanings does “loco” have?

“Loco” has 2 distinct senses listed in this dictionary. The most common is: crazy or out of one's mind (informal).

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Vocabulary lists that include loco:

Words with Spanish origins Words that end with O