plural of thirty

A decade starting with the year xx30, most usually the decade from 1930 to 1939. / The decade of one's life from age 30 through age 39. / (temperature, rates) The range between 30 and 39.

From or evoking the 31st through 40th years of a century (chiefly the 1930s).

plural of thirty-thirty

(firearms) A thirty calibre firearm designed for cartridges that originally held thirty grains of smokeless powder.

The cardinal number occurring after twenty-nine and before thirty-one, represented in Arabic numerals as 30.

(slang) A rack of thirty beers.

Obsolete spelling of thirty

(historical) United States Treasury notes, made during the Civil War, in denominations of $50 and above, bearing interest at the rate of seven and three tenths (thirty hundredths) percent annually. Within a few years they were all redeemed or funded.

The 1930s, especially in reference to the Dust Bowl of the Midwestern United States.