sunset

1 of 3

noun

sun·​set ˈsən-ˌset 

1

: the apparent descent of the sun below the horizon

also : the accompanying atmospheric effects

2

: the time when the upper limb of the sun disappears below the horizon as a result of the diurnal rotation of the earth

3

: a period of decline

especially : old age

sunset

2 of 3

adjective

: stipulating the periodic review of government agencies and programs in order to continue their existence

sunset laws

sunset

3 of 3

verb

sunsetted; sunsetting

1

transitive US : to cause or allow (something, such as a law) to lapse, end, or be terminated

… Obama offered an amendment … that would have sunsetted the merit-based evaluation system for immigrants after five years.

—Jake Tapper

In an effort to cut back on projects, Google decided to sunset Google Reader …

—Tristan Louis

2

intransitive US : to lapse or come to an end : expire

laws that will sunset at the end of the year

Since the credit will sunset at the end of 2016, its fate could rest in the hands of a new Congress and a new president—who might not necessarily see the value in reinstating the credit.

—Eric S. Peterson

Synonyms of sunset

Noun

• dusk
• night
• twilight
• evening
• sundown

Examples of sunset in a Sentence

Noun

We worked from sunrise to sunset.

the golden light of sunset

Recent Examples on the Web

Noun

Big emotional moments are punctuated by striking shots of fiery, mountainside sunsets and comforting, homestead greenery. — Ben Travers, IndieWire, 1 Oct. 2026

Food and drink From sunrise to sunset, breakfast to dinner, Oku Andalusia really gets it right. — Condé Nast, Condé Nast Traveler, 1 Oct. 2026

Adjective

Then be sure to read our roundups of the best cameras and lenses for astrophotography, along with our beginner's guide to photographing the post-sunset realm. — Anthony Wood, Space.com, 13 June 2026

Venus, Jupiter and Mercury parade together low in the post-sunset twilight sky for most of June. — Jamie Carter, Forbes.com, 31 May 2026

Verb

Elon Musk’s firm hasn’t been shy about wanting to sunset the Falcon 9 rocket that launches Crew Dragon, as well as the capsule, in favor of developing its Starship megarockets. — Adam Kovac, Scientific American, 28 Sep. 2026

Related Just this week, Newsom signed Senate Bill 180, which extends the state’s business incentive program, CalCompetes, through fiscal year 2032-33 after it was scheduled to sunset next year. — Gil Kaufman, Billboard, 16 Sep. 2026

Word History

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1

Adjective

1974, in the meaning defined above

Verb

1976, in the meaning defined at sense 1

Rhymes for sunset

• abet
• asset
• baguette
• banquette
• barbette
• beget
• beset
• binet
• briquette
• brunet
• brunette
• burette

Kids Definition

sunset

noun

sun·​set

-ˌset

1

: the apparent sinking of the sun below the horizon

also : the accompanying atmospheric effects

2

: the time at which the sun sets

Legal Definition

sunset

adjective

sun·​set

: having or being a provision stipulating the termination or repeal of something (as a law, grant, or insurance coverage) on a specified date

sunset laws requiring periodic review of programs to justify their continuance