noun, noun which may take the genitive case particle 'no'
Describes a technique, blow, or move that is intended to be fatal or decisive. Often used in fighting, martial arts, and sports, as well as metaphorically for a surefire method.
彼は必殺の一撃を放った。
He unleashed a deadly blow.
この技は彼の必殺パンチだ。
This technique is his knockout punch.
Compound of 必 (certainly) and 殺 (kill). The word originally referred to a technique that guarantees a kill, and later extended to any decisive or surefire move.