U+1F17E Negative Squared Latin Capital Letter O

U+1F17E was added in Unicode version 6.0 in 2010. It belongs to the block U+1F100 to U+1F1FF Enclosed Alphanumeric Supplement in the U+10000 to U+1FFFF Supplementary Multilingual Plane.

This character is a Other Symbol and is commonly used, that is, in no specific script. The character is also known as blood type O.

The glyph is not a composition. Its width in East Asian texts is determined by its context. It can be displayed wide or narrow. In bidirectional text it is written from left to right. When changing direction it is not mirrored. If its East Asian Width is “narrow”, U+1F17E forms a word with similar characters, which prevents a line break inside it. Otherwise it allows line breaks around it, except in some numeric contexts.

The CLDR project calls this character “O button (blood type)” for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: blood type, O.

This character is designated as an emoji. It will be rendered as monochrome character on conforming platforms. To enable colorful emoji display, you can combine it with Variation Selector-16: 🅾️ See the Emojipedia for more details on this character’s emoji properties.