The Plus Sign with Tilde Below 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+2A26 (decimal 10790).
Use ⨦ in HTML to render ⨦ on a web page.
On Windows you can type it with Alt+10790 (hold Alt and enter the number on the numeric keypad).
Yes — copying is completely free and unlimited, and works right in your browser with no sign-up.