adj, noun, slang ·3 syllables ·Moderate ·College level

Definitions

Noun

1. 1
   The person or thing in the twenty-first position.
2. 2
   One of twenty-one equal parts of a whole, usually written ¹⁄₂₁.
3. 3
   A party to celebrate a twenty-first birthday. informal

Adjective

1. 1
   The ordinal form of the number twenty-one. not-comparable

Adjective

1. 1
   coming next after the twentieth in position wordnet

Synonyms

All synonyms

21sttwenty-oneth

Example

More examples

"The twenty-first century starts in just a few years."

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.