Eye for eye and tooth for tooth.是什么意思？

Eye for eye and tooth for tooth.

以眼还眼,以牙还牙。

eye

n. 眼睛，视力，眼状物，风纪扣扣

例句
Gloria slid an appraising eye over the rest of the rack before reaching for the dress.
格洛丽亚以审视的眼光向货架上其余的衣服扫了一遍，才伸手去拿那件连衣裙。

for

prep. 为，为了，倾向于，关于，当作；conj. 因为，由于；

例句
I've come looking for a bit of advice.
我特来讨教。

and

conj. 和，与，而且，于是，然后，因此；

例句
I spend a lot on expensive jewelry and clothing...
我花很多钱购买昂贵的首饰和衣服。

tooth

n. 牙，齿，齿状部份；vt. 给…装齿；vi. 啮合；

例句
Many infants do not cut their first tooth until they are a year old.
很多婴儿到一岁大时才开始长牙。