lóu
used in 髑髏|髑髅[du2 lou2] and 骷髏|骷髅[ku1 lou2]
骷髅头
kū lóu tóu
a death's-head; depiction of a dead person's skull
髑髅
dú lóu
(literary) skull (of a dead person)
骷髅
kū lóu
human skeleton