drug/ dr^g /

1.noun [c] 
(prescribed) 药

This drug is prescribed to treat hay fever.
开的这种药是用来治疗花粉热的。
2.noun
(recreational) 毒品

Cocaine is a highly addictive drug.
可卡因是一种极为容易上瘾的毒品。
3.vt.[+person] [ animal] 
(sedate) 使麻醉

to be on drugs
吸毒
to take drugs
吸毒
hard/soft drugs
硬/软毒品