Adulterine

A·dul·ter·ine

Adulterine

a.
  1. Proceeding from adulterous intercourse. Hence: Spurious; without the support of law; illegal.
    When any particular class of artificers or traders thought proper to act as a corporation without a charter, such were called adulterine guilds.
    — Adam Smith.

Adulterine

n.
  1. An illegitimate child. [R.]