illicit

形容词 illicit:

1. contrary to accepted morality (especially sexual morality) or convention
2. contrary to or forbidden by law
   同义词：illegitimate, outlaw, outlawed, unlawful

1. Kept or done in secret, often in order to conceal an illicit or improper purpose.
   秘密的，暗中的保密的或秘密进行的，常为隐藏一个非法的或不正当的目的
2. A drug, especially an illicit or addictive one.
   麻醉剂尤指非法使用或使人上瘾的麻醉剂
3. A love affair, especially an illicit one.
   偷情尤指不正当的男女关系
4. He makes a lot of money by traffic illicit merchandise.
   他做违禁商品买卖赚了许多钱。

il.lic.it

adj.（形容词）
Not sanctioned by custom or law; unlawful.
非法的，不正当的：不为惯例或法律所允许的；不法的

来源：
Latin illicitus
拉丁语 illicitus
in- [not] * see in-
in- [不] *参见 in-
licitus [lawful] * see licit
licitus [合法的] *参见 licit

【引伸】
illic.itly
adv.（副词）
illic.itness
n.（名词）