How to say "addiction" in Japanese

Choosing the right word

中毒ちゅうどくJLPT N1approx.Common
noun (suffix)The common word for addiction proper, literally 'poisoning'; it covers dependence on substances such as alcohol or drugs, and is also used figuratively for being hooked on an activity.
私はテレビ中毒ちゅうどくです。↗
I'm a TV addict.
沼ぬまJLPT N1approx.Common
noun, noun (suffix)Slang, literally 'swamp': being so hooked on or obsessed with a hobby, game, or series that you have gotten sucked in. Informal use; not the word for serious substance dependence.

Use 中毒 for addiction in the serious sense, such as dependence on alcohol or drugs; use 沼, a slang term, for being hooked on or obsessed with a hobby, game, or interest.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

アディクションaddiction
常用癖じょうようへきaddiction
嗜癖しへきaddiction
惑溺わくできindulgence
ホリック-aholic (as in "workaholic")
中毒ちゅうどくaddiction
沼ぬまobsession
愛着あいじゃくaddiction

JLPT vocabulary levels are community estimates, not official (no official lists have been published since the 2010 revision).

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