yǐn​jūn​zǐ

addict

瘾君子 (癮君子) yǐn​jūn​zǐ
addict noun
a person who is addicted to narcotics or illegal drugs, such as opium

This rehabilitation center specializes in helping addicts overcome drug addiction.

chain smoker noun
a person who is heavily addicted to smoking tobacco

He's a long-time smoker who smokes two packs a day without fail.

Frequency

Movie subtitles
13.1 per million appears in 5% of films
Written text
0.468 per million

Sources

Definitions
CC-CEDICT