The armies of both countries were locked in a stand-off at the border, neither willing to retreat first.

stand-off 是由动词短语 stand off（保持距离）演变而来的复合名词。stand 表示"站立"，off 表示"离开、保持距离"。 stand-off 指双方僵持不下的状态，即"对峙"，通常形容军事冲突或谈判中双方都不愿让步的局面。