# loco

/ˈɫoʊkoʊ/ (US) · /lˈəʊkəʊ/ (UK) · CEFR B2 · Adjective

Source: https://englishreference.com/word/loco
Updated: 2026-08-15

## Definition

crazy or wild. You use this informal word to describe someone acting in a strange or silly way.

For teachers: mentally unstable or acting in a wild, irrational manner. Borrowed from Spanish; restricted to informal or colloquial registers.

## Examples

- The crowd went loco when the band started playing.
- He must be loco if he thinks he can finish all that work in one hour.
- The atmosphere in the stadium turned absolutely loco after the underdog team scored the winning goal in the final seconds of the match.

## Usage notes

- Often follows linking verbs like 'go' or 'be'.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.