Colon Equals \coloneqq

When to use Colon Equals

Typesets a definition relation with colon before equals. In source, start from the exact \coloneqq command instead of imitating the rendered glyph with Unicode characters or manual spacing. This keeps the expression editable and gives the renderer enough structure to apply mathematical spacing correctly.

Syntax

\coloneqq

The documented syntax belongs to mathtools. Keep every required argument, brace pair, and environment boundary intact when moving the command between an editor, Markdown processor, notebook, or publishing system.

Example

f(x)\coloneqq x^2

Rendered output

defined as

Copy and compatibility checks

• Copy \coloneqq exactly; changing its case or removing a leading backslash can turn it into plain text.
• Confirm that the destination loads mathtools before relying on this command.
• Render the example once, then inspect grouping, limits, scripts, and spacing before publishing.