illegitimate

adjective

il·​le·​git·​i·​mate ˌi-li-ˈji-tə-mət 

1

a

: not recognized as lawful offspring

b

: born of parents not married to each other

2

a

: not sanctioned by law : illegal

b

: not authorized by good usage

c

of a taxon : published but not in accordance with the rules of the relevant international code

3

: not rightly deduced or inferred : illogical

4

: departing from the regular : erratic

illegitimately adverb

Synonyms

• baseborn
• misbegotten
• natural
• spurious
• supposititious
• unfathered

Examples of illegitimate in a Sentence

She thinks that my concerns are illegitimate.

They were fired from their jobs for illegitimate reasons.

Recent Examples on the Web

For years, Putin claimed that direct talks with Ukraine were impossible because President Volodymyr Zelensky’s government was illegitimate and, more important, Ukraine wasn’t a real country—merely a proxy for the American imperial project. —Andrew Ryvkin, The Atlantic, 16 June 2025

Putin has insisted that Ukraine must replace its leadership through elections, describing Zelensky's rule as illegitimate. —David Faris, MSNBC Newsweek, 12 Apr. 2025

This secret-keeping tradition kept President François Mitterrand’s illegitimate daughter hidden for years. —Saskya Vandoorne, CNN Money, 27 May 2025

Maduro, whose reelection last year to a third term has been condemned internationally as illegitimate, also has cracked down on his political opponents. —Mark Sherman, Chicago Tribune, 19 May 2025

Word History

First Known Use

1536, in the meaning defined at sense 1a

Rhymes for illegitimate

• legitimate

Kids Definition

illegitimate

adjective

il·​le·​git·​i·​mate ˌil-i-ˈjit-ə-mət 

1

: born of a father and mother who are not married

2

: illegal

illegitimately adverb

Legal Definition

illegitimate

adjective

il·​le·​git·​i·​mate ˌi-li-ˈji-tə-mət 

1

: not recognized by the law as offspring

specifically : born out of marriage

Note: An illegitimate child is usually legitimated by his or her parents' later marriage. Illegitimate children generally have the same inheritance rights under intestate successions as legitimate children; statutes limiting their inheritance rights have been found to violate the equal protection clause.

2

: not valid according to law

illegitimate noun