Suicide or any suicidal action.
Ceremonial suicide by disembowelment, as by slicing open the abdomen with a dagger or knife: formerly practised in Japan by the Samurai when disgraced or sentenced to death.
An act against one's own interests.
Synonym of suicide (“beverage combining all available flavors at a soda fountain”)
Used other than figuratively or idiomatically: see swamp, water.