What does illegitimate mean?
Illegitimate is an adjective meaning unlawful, unauthorized, or contrary to established rules and principles. It is especially common in legal, political, and ethical contexts, as in “illegitimate government” or “an illegitimate use of force.” The word also has a long-established family-law sense: describing a child born to parents who were not married to each other. Although that usage remains accurate, neutral modern phrasing often favors “child born outside marriage,” since the older term may imply shame or illegitimacy. In general usage, illegitimate conveys a stronger sense of violation than merely “unwanted” or “unusual”: something illegitimate is denied recognition or authority because it conflicts with law or accepted principles. The word is understood in British and American English and is especially suited to formal discussion.
adjectiveNot conforming to law or established rules; unlawful or unauthorized. It can also mean born to parents who were not married to each other.
- Contrary to law, accepted rules, or recognized authority; unlawful or unauthorized.
- Born to parents who were not married to each other.
- Not valid, proper, or justifiable according to accepted principles.
"The court ruled that the seizure of private property had been illegitimate."
"The committee condemned the illegitimate interference in the election."
"Her grandfather was born an illegitimate child and was later formally recognized by his father."
One word can describe both a child born outside marriage and a government that lacks lawful authority.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does illegitimate come from?
Illegitimate was formed in late Middle English from the Latin adjective illegitimus, meaning “not lawful.” The Latin word combines the negative prefix in- with legitimus, “lawful,” which is related to lex, the Latin word for law. The same legal root underlies English cognates including legal, legality, legalize, and legitimate.
Related word forms
How illegitimate is actually used
The word is formal and often legalistic. In modern discussion of family relationships, “child born outside marriage” is sometimes preferred to “illegitimate child” because the traditional term can sound stigmatizing.
Easily confused with illegitimate
Illegible means impossible or difficult to read, whereas illegitimate means unlawful, unauthorized, or outside marriage.
Illicit describes an activity that is specifically forbidden by law, while illegitimate is broader and can also mean contrary to accepted rules or principles.