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.
Suicide or any suicidal action.
An act against one's own interests.
selfimmolation
How often have the words hara-kiri and selfimmolation occurred in a corpus of books? (source: Google Ngram Viewer )