How to say "knockout" in Japanese

• 必殺ひっさつCommon
  no-adjectiveCovers the 'knockout (blow)' sense: a blow that finishes an opponent, with the strong nuance of certain death. It suits dramatic or figurative descriptions of a decisive, deadly strike.
• ノックアウト
  noun, suru verb, transitive verbThe loanword, matching 'knockout' directly: the boxing sense, a fight ended by a knockout or the state of being knocked out. It is less common, and the more literal choice of the two.
  彼かれはノックアウト勝かちした。↗

  He won the fight by a knockout.

For a deadly, finishing 'knockout blow' with dramatic force, use 必殺; for the boxing term itself — a fight ended by knockout or the resulting state — use the loanword 「ノックアウト」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 必殺ひっさつbringing certain death
• ノックアウトknockout