名詞 fallback:

1. to break off a military action with an enemy
   同義詞：disengagement, pullout

fall.back

n.（名詞）

Something to which one can resort or retreat.
退路：某人可以憑借或隱退的某物
A retreat.
退卻
Computer Science A mechanism for carrying forth programmed instructions despite malfunction or failure of the primary device.
【計算機科學】 低效運行，撤退：即使主要設(shè)備失靈或產(chǎn)生故障也能繼續(xù)按編定的指令工作的機械
Something that falls back:
降落物：
例句：
the fallback of a huge explosion.
一次大爆炸的降落物

adj.（形容詞）
Of, relating to, or constituting a resort or place of retreat:
后退的，應(yīng)變的：（組成）撤退的手段或地方的，與其有關(guān)的：
例句：
a fallback proposal; a fallback position behind our own lines.
撤退計劃；在我們戰(zhàn)線后的撤退地點