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illicit vs. illegal

[ih-lis-it] / ɪˈlɪs ɪt /

adjective

  1. not legally permitted or authorized; unlicensed; unlawful.

    Synonyms:
    prohibited, illegitimate
  2. disapproved of or not permitted for moral or ethical reasons.

[ih-lee-guhl] / ɪˈli gəl /

adjective

  1. forbidden by law or statute.

    Synonyms:
    unlicensed, illicit, illegitimate, unlawful
  2. contrary to or forbidden by official rules, regulations, etc..

    The referee ruled that it was an illegal forward pass.

noun

  1. Informal: Disparaging and Offensive. illegal alien.