# \lambda

The λ symbol (Greek small letter lamda, U+03BB), written as \lambda in LaTeX math mode.

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

## Metadata

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

## Syntax

```latex
\lambda
```

Takes no arguments.

## Common tasks

### How to write a Greek lambda

```latex
\lambda
```

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

### How to write an eigenvalue

```latex
Av=\lambda v
```

[Open in Playground](https://play.texform.dev/?input=Av%3D%5Clambda+v)

### How to write a Poisson rate

```latex
X\sim\mathrm{Poisson}(\lambda)
```

[Open in Playground](https://play.texform.dev/?input=X%5Csim%5Cmathrm%7BPoisson%7D%28%5Clambda%29)

## Usage frequency

8.26% of formulas in the measured corpus contain this entry, rank 7 of 474 entries with frequency data.

## In TeXForm

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