# illegitimate

/ˌɪɫɪˈdʒɪtəmɪt/ (US) · /ɪlədʒˈɪtɪmət/ (UK)

Source: https://englishreference.com/word/illegitimate
Updated: 2026-08-08

## Senses

### 1. not legal

adjective · CEFR B2

not allowed by the law or by official rules.

For teachers: not in accordance with the law or established legal standards.

- The court ruled that the government's use of power was illegitimate.
- The opposition party argued that the election results were illegitimate due to widespread reports of voter intimidation.

### 2. born to unmarried parents

adjective · CEFR C1 · Formal

born to parents who were not married to each other.

For teachers: born of parents not lawfully married to each other at the time of birth.

- In the past, being an illegitimate child could cause many social problems.
- The historical novel focuses on the struggles of an illegitimate son trying to claim his rightful inheritance from a noble family.

Usage: In modern legal and social contexts, this term is often replaced by 'born out of wedlock' or simply avoided due to its historical stigma.

Teaching tip: This sense is historically significant but can be offensive in modern conversation; students should use it only when discussing history or law.

### 3. not logical

adjective · CEFR C1 · Academic

not following the rules of logic or clear thinking.

For teachers: not correctly deduced or inferred according to the principles of logic.

- That is an illegitimate conclusion because it is not based on the facts.
- The professor pointed out that the student's argument relied on an illegitimate inference that ignored the primary data set.

### 4. botany

adjective · CEFR C2 · Technical

a technical term for how certain flowers are fertilized.

For teachers: referring to the fertilization of pistils by stamens of a different length in heterostylous plants.

- The scientist studied the illegitimate pollination of the primrose flowers.
- Illegitimate crosses in trimorphic species often result in significantly reduced seed production compared to legitimate pairings.

### 5. a person

noun · CEFR C2 · Archaic · Formal

an old-fashioned and often rude way to describe a person born to unmarried parents.

For teachers: a person born to parents who are not married to each other.

- The king had several children, but only one was not an illegitimate.
- Under the old laws of the realm, an illegitimate could not inherit the crown regardless of their father's wishes.

Teaching tip: This noun form is extremely rare in modern English and is usually replaced by the adjective phrase 'illegitimate child'.

### 6. to make invalid

verb · CEFR C2 · Formal

to make something no longer legal or official.

For teachers: to render something illegitimate or to declare it as lacking legal status.

- The new law might illegitimate many existing contracts.
- The decree served to illegitimate the previous administration's treaties, causing a diplomatic crisis.

## Examples

- The judge ruled that the evidence was illegitimate.
- The opposition party claimed the election results were illegitimate due to widespread voting irregularities.
- While the regime maintained a veneer of democracy, international observers argued that its power was illegitimate because it lacked the genuine consent of the governed.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.