The Ideographic Full Stop symbol (。). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Punctuation.
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+3002 (decimal 12290).
Use 。 in HTML to render 。 on a web page.
On Windows you can type it with Alt+12290 (hold Alt and enter the number on the numeric keypad).
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