# groupoid

## English[edit]

### Etymology[edit]

### Noun[edit]

**groupoid** (*plural* **groupoids**)

- (algebra) A magma: a set with a total binary operation.
- (algebra and category theory) A set with a partial binary operation that is associative and has inverses and identities.
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**groupoid**is a category in which every morphism is an isomorphism.

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