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

That period, in 2017, was defined by public demonstrations of resistance, a flurry of new liberal groups and a palpable anger over an election outcome many in the party saw as illegitimate. —Reid J. Epstein, New York Times, 24 Jan. 2025

Teams with low absenteeism judge calling in sick for illegitimate reasons. —Lieke Ten Brummelhuis, Forbes, 23 Jan. 2025

However, some illegitimate brands may sell contaminated or mislabeled products. —Rowan Briggs, The Mercury News, 17 Jan. 2025

From a phone in the Kremlin, Burns listened to the Russian leader recite his usual bill of grievances—an expansionist NATO threatened Russian security; Zelensky was the illegitimate leader of a non-country. —Shane Harris, The Atlantic, 17 Jan. 2025

Word History

First Known Use

1536, in the meaning defined at sense 1a

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