thirties

(also 30s, 30’s)

/ˈθɜr·t̬iz/ pl n

Definition

› the numbers 30 through 39: My sisters are in their thirties (= between 30 and 39 years old). The temperature is expected to be in the thirties (= between 30° and 39°) tomorrow. These dresses were fashionable in the thirties (= between 1930 and 1939).

(Definition of thirties pl n from the Cambridge Academic Content Dictionary © Cambridge University Press)