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

• 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

In addition, as FanSided Mets writer Stephen Parello pointed out on Monday, Boras may also be failing to take into account another factor working against Alonso — the expiration of baseball's collective bargaining agreement, which happens following next season. —Jon Vankin, MSNBC Newsweek, 27 Oct. 2025

Selling a put under those conditions, with roughly 60 days to expiration, positions the seller to capture elevated option premium while capturing the tendency for prices to revert toward the mean. —Michael Khouw, CNBC, 27 Oct. 2025

The potential cost increases are tied to the expiration of pandemic-era subsidies at the end of the year. —Molly Beck, jsonline.com, 27 Oct. 2025

Premium costs will soon explode for many consumers because of the expiration of certain federal subsidies that kept those monthly costs low. —NPR, 26 Oct. 2025

Word History

First Known Use

1526, 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