ninety · number /ˈnaɪn.ti/Full view
A2 the number 90
Dictionary examples:

eighty, ninety, a hundred

Ninety percent of the people surveyed were in favour.

Learner example:

It costs ninety euros, [a] good price. (Key English Test; A2; Catalan)

(be) in your nineties
B2 to be aged between 90 and 99
Dictionary example:

He is in his nineties now.

the nineties
B2 the years from 1990-1999
Dictionary example:

I spent most of the nineties travelling around the world.

Learner example:

Another aspect which shows us the danger that the car represents to human life in the nineties [is] pollution. (First Certificate in English; B2; Portuguese)

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