1. the numbers from 20 to 29, especially when referring to temperature, age, or years in a century
Usage: plural form
2. the decade from 1920 to 1929
Usage: historical period; often capitalized as ‘the Twenties’

Examples

• The temperature will be in the twenties all week.
• She’s in her early twenties and just graduated from college.
• My grandfather was born in the twenties.
• The Twenties were known for jazz music and economic prosperity.
• He’s somewhere in his mid-twenties.
• The stock market crashed at the end of the twenties.
• It’s going to be a cold night with temperatures in the low twenties.