# ninety

/ˈnaɪnti/ (US) · /nˈaɪnti/ (UK) · CEFR A1 · Noun

Source: https://englishreference.com/word/ninety
Updated: 2026-05-02

## Definition

the number 90. It comes after eighty-nine and before ninety-one.

For teachers: the cardinal number equivalent to the product of nine and ten. Functions as both a noun and a determiner depending on the syntactic context.

## Examples

- My grandfather is ninety years old.
- The speed limit on this stretch of the highway is ninety kilometers per hour.
- The temperature in the desert rose to nearly ninety degrees by midday, forcing the researchers to seek shelter until the sun began its descent.

## Pitfalls

- Not "ninty" but "ninety" — Learners often mistakenly drop the 'e' from 'nine' when adding the suffix '-ty'.

## Usage notes

- When used as a determiner, it precedes the noun it modifies. In its plural form, 'nineties', it refers to a decade or a range of temperatures.

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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.