#
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.

## Related pages

Last revised on September 28, 2022 at 14:43:28.
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