名詞 backlash:

1. a movement back from an impact
   同義詞：recoil, repercussion, rebound
2. an adverse reaction to some political or social occurrence

動詞 backlash:

1. come back to the originator of an action with an undesired effect
   同義詞：backfire, recoil

1. The fall of the fascist dictatorship was followed by a left-wing backlash.
   法西斯專政的垮臺引起左翼運動的高漲。

back.lash

n.（名詞）
A sudden or violent backward whipping motion.
后沖，反撞：突然或強烈的向后抽動
An antagonistic reaction to an earlier action:
激烈反應，激烈反對：對一個較早行動的對抗性反應：
例句：
.White backlash increases as the pressure for change in South Africa mounts.(Masipula Sithole)
.隨著南非要求變化活動的壓力的增加，白人的對抗情緒也增加了.(馬西普拉·西索爾)

A snarl formed in the part of a fishing line that is wound around the reel.
纏結：在纏繞著線輪的釣線部分上形成的纏結
The play resulting from loose connections between gears or other mechanical elements.
齒輪隙：由于齒輪或其它機械裝置之間的連接處松動而造成的間隙

【引伸】
back.lash.
v.（動詞）