“战友”常见的英文表达是 comrade-in-arms ，也可简化为 comrade（不过“comrade”含义较宽泛，也可指同志、伙伴等） ，或用 battle buddy（美式英语中较常用，侧重于战场上并肩作战的伙伴） 。
They were comrades-in-arms during the war, sharing both hardships and victories.
（他们在战争期间是战友，同甘共苦，共享胜利。）
My old comrades from the army often get together to reminisce about the past.
（我那些军队里的老战友们经常聚在一起回忆过去。）
In the military, a battle buddy is someone you can always rely on.
（在军队里，战友是你永远可以依靠的人。）