also: どしうち
friendly fire; accidental killing of allies
Refers to accidentally attacking or killing one's own side in battle or conflict. Often used in military or historical contexts.
On the battlefield, they wore markers to avoid friendly fire.
The incident was due to friendly fire.
internecine strife; infighting among allies
Extended meaning: conflict or struggle within a group that should be united. Can be used metaphorically for political or organizational infighting.
Infighting within the party led to the election loss.
This is no time for fighting among ourselves.
内輪もめ refers to internal quarrels or family disputes, often petty, while 同士討ち emphasizes the irony of allies harming each other, with a stronger connotation of betrayal or tragic mistake.
仲間割れ means a split or falling-out among comrades, focusing on the breakdown of relationships, whereas 同士討ち highlights the active conflict or harm between them.
Common variant; 打ち is a simpler character for 'striking' and is frequent in news contexts.
Standard kanji spelling; 討ち conveys 'attacking/defeating' clearly.
Contracted reading; less common but recognized.
Compound of 同士 (dōshi, 'comrades, fellows') and 討ち/打ち (uchi, 'striking, attacking'). The literal meaning is 'comrade-striking', naturally extended to both accidental friendly fire and deliberate infighting.