A symbol representing Blood Type O. Displayed as the letter O on a red background.
O Button (Blood Type) was approved as part of Unicode 6.0 in 2010 under the name “Negative Squared Latin Capital Letter O” and added to Emoji 1.0 in 2015.
U+1F17E
U+FE0F
?️ Negative squared latin capital letter o
?️ Variation selector-16