thirty

From Wiktionary
thirty is one of the 1000 most common headwords.
thirteen - thirty - this
English numbers (edit)
300
 ←  20  ←  29 30 31  →  40  → 
3
    Cardinal: thirty
    Ordinal: thirtieth

Pronunciation[change]

Determiner[change]

Determiner
thirty

  1. (number) (indefinite) (plural) (count) (ordinal thirtieth) The number 30.
    I had my first child when I was thirty years old.

Noun[change]

Singular
thirty

Plural
thirties

  1. The number 30.
    Three tens is thirty.