noun
eternity
ih-TER-nuh-tee/ɪˈtɜːrnəti/
Existence or duration without end.
The short wait feels like an eternity to her.

Etymology
The enduring or everlasting base becomes a noun naming that quality. Eternity first meant the quality of being eternal, then came to mean infinite time itself.
In context
a day can last a second, blow by like a whirlwind or it can become a whole eternity.
More examples
- A minute feels like an eternity when you're holding your breath.
- Their vows promise a love that lasts for eternity.
- The idea of eternity challenges our ordinary sense of time.
Forms
eternity · eternities
eternal adjective — Lasting forever; having no end.
eternally adverb — Forever or for an endless time.
Similar words
- infinity
- Infinity also describes limitless space or quantity, not just time.
- perpetuity
- Perpetuity emphasizes something continuing forever, especially in legal contexts.