# loopy

/ˈɫupi/ (US) · /lˈuːpi/ (UK) · CEFR B2 · Adjective

Source: https://englishreference.com/word/loopy
Updated: 2026-10-17

## Definition

a little crazy or silly in a funny way. You use it when someone acts strange, often because they are tired, happy, or joking around.

For teachers: describing someone mildly eccentric, silly, or mentally unfocused, often from tiredness, amusement, or intoxication. Often suggests temporary odd behaviour rather than serious mental illness.

## Examples

- You sound a bit loopy after no sleep.
- After the long night shift, the nurses get loopy and laugh at small jokes.
- Sleep deprivation made his thinking loopy, so his normally careful plan came out as a wild mix of good ideas and nonsense.

## Usage notes

- Typically used predicatively after 'be', 'get', or 'sound' rather than before a noun.

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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.