# nLab opposite 2-category

Contents

### Context

#### 2-Category theory

2-category theory

Definitions

Transfors between 2-categories

Morphisms in 2-categories

Structures in 2-categories

Limits in 2-categories

Structures on 2-categories

# Contents

## Definition

A 2-category $K$ has three different opposites (two independent):

• The $1$-cell dual $K^{op}$, in which the $1$-cells but not the $2$-cells are reversed.
• The $2$-cell dual $K^{co}$, in which the $2$-cells but not the $1$-cells are reversed.
• The bidual $K^{co op}$ in which both $1$-cells and $2$-cells are reversed.

Last revised on September 28, 2022 at 14:43:28. See the history of this page for a list of all contributions to it.