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unlawful vs. illegal

[uhn-law-fuhl] / ʌnˈlɔ fəl /

adjective

  1. not lawful; contrary to law; illegal.

    Synonyms:
    illicit
  2. born out of wedlock; illegitimate.

    Synonyms:
    natural, bastard
[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.