illegitimate

(noun) the illegitimate offspring of unmarried parents. Synonyms: bastard, by-blow, love child, illegitimate child, whoreson.

(adj) contrary to or forbidden by law. Synonyms: illicit, outlaw(prenominal), outlawed, unlawful. Examples: "An illegitimate seizure of power." "Illicit trade." "An outlaw strike." "Unlawful measures."

(adj) of marriages and offspring; not recognized as lawful. Synonyms: illegitimate (vs. legitimate).