From Longman Dictionary of Contemporary Englishninetynine‧ty /ˈnaɪnti/ ●●● S3 W3 number 1 HMNthe number 902 → the nineties3 → be in your nineties4 → in the nineties —ninetieth adjective her ninetieth birthdayOrigin ninety Old English nigontig, from nigon “nine”
