freebase

• vt. 加热精炼；加热吸用
• vi. 加热精炼或吸用可卡因
• n. 毒品（俚语）

free, 纯的，免于其它杂质的。base, 基，基础。用于指精炼可卡因。

freebase

1980 (noun and verb), in reference to cocaine. As a chemical process, it returns a salt form of an alkaloid to its pure form. Related: Freebased; freebasing.

1. The drug is variously known as crack or freebase.

这种毒品的叫法五花八门,有人称为crack,也有人叫它freebase.

来自《简明英汉词典》