<P> Skull and crossbones is a symbol of a human skull with two long bones crossed below it . It is used in several contexts: </P> <Ul> <Li> Skull and crossbones (symbol), as a symbol of death and especially as a memento mori on tombstones, a warning symbol of poisonous substances and danger </Li> <Li> Skull and crossbones (military), in variations used by several military forces </Li> <Li> Skull and crossbones (fraternities and sports), used also by secret societies </Li> <Li> Skull and crossbones (Spanish cemetery) "campo santo", used to mark the entrances to cemeteries </Li> <Li> Unicode represents the symbol "☠" in its Miscellaneous Symbols block . </Li> </Ul> <Li> Skull and crossbones (symbol), as a symbol of death and especially as a memento mori on tombstones, a warning symbol of poisonous substances and danger </Li> <Li> Skull and crossbones (military), in variations used by several military forces </Li>

What does the skull and cross bones mean
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