SEPPUKU

Seppuku (Japanese: "cutting the belly") is a form of Japanese ritual suicide by disembowlment. Seppuku is also known as hara-kiri "belly-cutting" and is written with the same kanji as seppuku but in reverse order with an okurigana. In Japanese, hara-kiri is a colloquialism, seppuku being the more formal term. Samurai (and modern adherents of bushido) would use seppuku, whereas ordinary Japanese (who in feudal times as well as today looked askance at the practice) would use hara-kiri. Hara-kiri is the more common term in English, where it is often mistakenly rendered "hari-kari."
The practice of committing seppuku at the death of one's master is known as oibara; the ritual is similar.