illegitimate

Adjective

illegitimate (comparative more illegitimate, superlative most illegitimate)

1. Not conforming to known principles, or established or accepted rules or standards.
   • […] it may be impossible to convince them that the illegitimate power which they obtain, by degrading themselves, is a curse […]1791 (date written), Mary Wollstonecraft, “The Prevailing Opinion of a Sexual Character Discussed”, in A Vindication of the Rights of Woman: With Strictures on Political and Moral Subjects, London...
   • The so-called interstellar space […] has not the properties of ordinary space. It will not conduct sound, nor can a human being move through it. It is therefore illegitimate to measure it in miles.1927, J. B. S. Haldane, “Possible Worlds”, in Possible Worlds and Other Essays, London: Chatto and Windus

   Synonyms:

   invalid, nonstandard

   Antonyms:

   legitimate, valid, acceptable, allowable, legit, leveful, licit, permissible, rightful, rulable

2. Not in accordance with the law.
   • […] if things went on at this rate it would be doubtful soon whether ever again he would be able to win another election by methods legitimate or illegitimate.1914, Theodore Dreiser, chapter 54, in The Titan, New York: John Lane, page 475

   Synonyms:

   illegal, illicit, unlawful, crimeful, criminal, lawbreaking, nonlawful, outlawed, wrongful

   Antonyms:

   legal, legitimate, de jure, lawful, licit, rightful

3. Not sanctioned by marriage.
   • If we credit the scandal of the former [i.e. his enemies], Artaxerxes sprang from the illegitimate commerce of a tanner’s wife with a common soldier.1783, Edward Gibbon, chapter 8, in The History of the Decline and Fall of the Roman Empire, volume 1, London: W. Strahan and T. Cadell, page 317
   • His illegitimate birth deprived him of the influence of a father until perhaps his fifth year […]1916, chapter 6, in Abraham Brill, transl., Leonardo da Vinci: A Psychosexual Study of an Infantile Reminiscence, New York: Moffat, Yard, page 118

   Antonyms:

   legitimate

   1. Born to unmarried parents.
      • an illegitimate child
      • I am a bastard begot, bastard instructed, bastard in mind, bastard in valour, in every thing illegitimate.c. 1602 (date written), William Shakespeare, “The Tragedie of Troylus and Cressida”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and...
   2. (dated) Having a child or children with a person to whom one is not married.
      • She had only to collect her memories, which proved to her that “anybody” regarded the illegitimate children as more rightfully to be looked shy on and deprived of social advantages than illegitimate fathers.1876, George Eliot [pseudonym; Mary Ann Evans], chapter 27, in Daniel Deronda, volume (please specify |volume=I to IV), Edinburgh; London: William Blackwood and Sons, →OCLC
      • I heard last night that a what-do-you-call it?—claimant?—has arrived who says Pat Wayne is his illegitimate father.1935, Carolyn Wells, chapter 13, in The Beautiful Derelict, New York: Triangle Books, page 222
4. Not correctly deduced.
   • an illegitimate inference
   • […] in natural things we must have recourse […] to experience. And all reasoning that is not supported so, ought to be repudiated, or at least suspected to be illegitimate.1658, Kenelm Digby, A Late Discourse […] Touching the Cure of Wounds by the Powder of Sympathy, London: R. Lownes and T. Davies, page 75

   Synonyms:

   illogical, invalid

   Antonyms:

   legitimate, logical, valid

5. Not authorized by good usage; not genuine.
   • an illegitimate word

   Synonyms:

   bogus, ingenuine, spurious, artificial, bad, bollocks, concocted, counterfeit, ersatz, fabricated

   Antonyms:

   bona fide, legitimate, actual, authentic, genuine, legit, lubish, non-fake, pukka, real

6. Involving the fertilization of pistils by stamens not of their own length, in heterogonously dimorphic and trimorphic flowers.
   • illegitimate union; illegitimate fertilization
   • […] the legitimate unions between the two forms of the above nine species of Primula are much more fertile than the illegitimate unions; although in the latter case pollen was always taken from a distinct plant of the same form.1877, Charles Darwin, chapter 1, in The Different Forms of Flowers on Plants of the Same Species

   Antonyms:

   legitimate

Noun

illegitimate (plural illegitimates)

1. A person born to unmarried parents.
   • Her father and mine was a shameless man and of all his illegitimates I am the most unfortunate and poverty stricken.1966, Jean Rhys, Wide Sargasso Sea, New York: Norton, Part 2, p. 96

   Synonyms:

   natural child, lovechild, bastard

Verb

IPA/ɪlɪˈd͡ʒɪtɪmeɪt/US[ɪlɨˈd͡ʒɪɾəmeɪt]

illegitimate (third-person singular simple present illegitimates, present participle illegitimating, simple past and past participle illegitimated)

1. (transitive) To make illegitimate.