expiration

noun

ex·​pi·​ra·​tion ˌek-spə-ˈrā-shən 

1

a

: the last emission of breath : death

b(1)

: the act or process of releasing air from the lungs through the nose or mouth : exhalation

(2)

: the escape of carbon dioxide from the body protoplasm (as through the blood and lungs or by diffusion)

2

: the fact of coming to an end or the point at which something ends : termination

Synonyms of expiration

• demise
• termination
• death
• dissolution

Examples of expiration in a Sentence

one month after the expiration of the contract

directed that upon her expiration her splendid Italian-style villa be given to the public as a museum

Recent Examples on the Web

Selling calls against a long position is standard procedure for many investors, but using strikes that are in the money with more than two years to expiration looks like something different. — Oliver Renick, CNBC, 7 Oct. 2026

That drop coincided with the expiration of enhanced premium tax credits, which made marketplace coverage significantly more affordable, after Congress declined to extend them. — Amber Bellazaire, Washington Post, 5 Oct. 2026

Lauren Truslow is chief executive of 3D Enviro, a Virginia company that does hazardous materials abatement with a handful of workers affected by the TPS expiration for El Salvador. — Andrea Castillo, Los Angeles Times, 3 Oct. 2026

The drop in sales was widely expected thanks to the expiration of the $7,500 federal tax credit for electric vehicles on September 30, 2025. — Andrew J. Hawkins, The Verge, 2 Oct. 2026

Word History

First Known Use

circa 1530, in the meaning defined at sense 1a

Phrases Containing expiration

• expiration date

Rhymes for expiration

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Kids Definition

expiration

noun

ex·​pi·​ra·​tion ˌek-spə-ˈrā-shən 

1

a

: the expelling of air from the lungs in breathing

b

: air or vapor expelled from the lungs

2

: the fact of coming to an end

Medical Definition

expiration

noun

ex·​pi·​ra·​tion ˌek-spə-ˈrā-shən 

1

a(1)

: the act or process of releasing air from the lungs through the nose or mouth : exhalation

(2)

: the escape of carbon dioxide from the body protoplasm (as through the blood and lungs or by diffusion)

b

archaic : the last emission of breath : death

2

: something produced by breathing out