WordWeb Online

1. Contrary to or forbidden by law
   "an illegitimate seizure of power";
   - illicit, outlaw, outlawed, unlawful
    
2. Of marriages and offspring; not recognized as lawful

1. A child with parents that are not married to each other
   - by-blow, love child, illegitimate child

Derived forms: illegitimates

See also: adulterine, base [archaic], baseborn [archaic], bastardly [archaic], fatherless, illegal, invalid, left-handed, misbegot [archaic], misbegotten [archaic], spurious [archaic], unauthorised [Brit], unauthorized, unlawful, wrongful

Type of: issue, offspring, progeny

Antonym: legitimate

Encyclopedia: Illegitimate