Thirties

How to spell thirties

8 letters · 2 syllables

How to pronounce thirties

Say the part in capitals loudest.

What does thirties mean?

1. nounThe numbers, ages, or years from thirty to thirty-nine, taken as a group.

Thirties in a sentence

• She bought her first house in her early thirties.

• The building was designed in the late thirties, just before the war.

Where does thirties come from?

Language of origin: Germanic

This word descends from the Old English thritig, which combined threo, meaning 'three', with the suffix -tig that marked a multiple of ten, giving the literal sense of 'three tens'. That same -tig element survives in the modern ending -ty across twenty, forty, fifty and the rest of the tens. The plural 'thirties' came into regular use to describe a span of numbers grouped by their tens digit, whether ages, calendar years, or measured quantities. By the nineteenth and twentieth centuries it was firmly settled as the way English speakers refer to a person's fourth decade of life or to the years of a century from the thirtieth to the thirty-ninth. The spelling trap is the shift from the -y of 'thirty' to the -ies of the plural, and the unstressed middle that makes the 'thir' feel slippery to write.

How the word is built

• thir- (from Old English thrie/threo: three)
• -ty (a multiple of ten)
• -ies (plural)