# Penrose triangle

## Contents

## English[edit]

### Etymology[edit]

After Roger Penrose (1931-), English mathematician, who popularised it in the 1950s.

### Noun[edit]

**Penrose triangle** (*plural* **Penrose triangles**)

- An optical illusion depicting an impossible solid object made of three straight beams of square cross section which meet pairwise at right angles at the vertices of the triangle they form.