comrade in arms; war buddy; fellow soldier
Refers to a companion with whom one has shared military service or battle experience. Carries a strong emotional bond of shared hardship.
彼は戦友を決して忘れなかった。
He never forgot his comrades in arms.
戦友会で昔の仲間と再会した。
I reunited with old buddies at the veterans' reunion.
He is honored as a fallen comrade in arms.
He lost many comrades in the war.
I fought on the front lines together with my war buddies.