The Colon Equals symbol (≔). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Math.
The quickest way is to copy ≔ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
≔ is U+2254 (decimal 8788).
Use ≔ in HTML to render ≔ on a web page.
On Windows you can type it with Alt+8788 (hold Alt and enter the number on the numeric keypad).
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