noun

1. A person born to unmarried parents.

Synonyms: bastard, lovechild, natural child

verb

1. To make illegitimate.

adjective

1. Not conforming to known principles, or established or accepted rules or standards.

2. Not in accordance with the law.

3. Not sanctioned by marriage.

Synonyms: illegal, illicit, unlawful, illogical, invalid, invalid, spurious