# \psi

The ψ symbol (Greek small letter psi, U+03C8), written as \psi in LaTeX math mode.

https://texform.dev/latex/symbols/psi

## Metadata

| Field | Value |
| --- | --- |
| Topic | [Greek letters](https://texform.dev/latex/topics/greek) |
| Packages | base |
| Allowed mode | math |
| Glyph | ψ |
| Unicode | U+03C8 GREEK SMALL LETTER PSI |
| Delimiter | No |

## Syntax

```latex
\psi
```

Takes no arguments.

## Common tasks

### How to write a Greek psi

```latex
\psi
```

[Open in Playground](https://play.texform.dev/?input=%5Cpsi)

### How to write a wave function

```latex
\psi(x,t)
```

[Open in Playground](https://play.texform.dev/?input=%5Cpsi%28x%2Ct%29)

### How to write a ket psi

```latex
\lvert\psi\rangle
```

[Open in Playground](https://play.texform.dev/?input=%5Clvert%5Cpsi%5Crangle)

## Usage frequency

3.91% of formulas in the measured corpus contain this entry, rank 31 of 474 entries with frequency data.

## In TeXForm

TeXForm parses this entry as a character leaf mapped to U+03C8 (GREEK SMALL LETTER PSI).