It is a white or gray skull with a pair of bones crossing behind it, such as a pirate flag or a poison symbol.
Can represent various concepts of death or danger, such as dying from laughter or killing it with great skill. Can also represent a variety of pirate characters or mascots.
Popular around Halloween. Not to be confused with ? Skull, though their applications may overlap.
Skull and Crossbones was approved as part of Unicode 1.1 in 1993 and added to Emoji 1.0 in 2015.
U+2620
U+FE0F
☠️ Skull and crossbones
☠️ Variation selector-16