n.

1. 抽出；拔出；榨出[U][C][（+from）]
   Her teeth are so bad that she needs five extractions.

   她的牙太糟，得拔掉五颗。

2. 选取；摘录[U][C]
3. 血统；出身[U]
   He comes from a family of Irish extraction.

   他出身于一个有爱尔兰血统的家庭。

4. 【数】开方

n.

1. the action of extracting.
2. ethnic origin:
   he's of Polish extraction.