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

And yet, even though he was part of the coalition, 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

Noun

• dusk
• night
• evening
• twilight
• 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

From the Southern Hemisphere, Mars will be in the northwest after sunset. —Jesse Emspak, Space.com, 25 June 2025

The post began with a photo of the actress smiling from ear to ear in front of a sunset. —Ingrid Vasquez, People.com, 24 June 2025

Adjective

Add an elegant outdoor sconce for some post-sunset flow and a cozy pillow. —Sofia Quintero, ELLE Decor, 28 Mar. 2023

The solar system’s largest planet this week takes a bow and departs the post-sunset night sky for many months. —Jamie Carter, Forbes, 26 Mar. 2023

Verb

At the center of the bill is an extension to Mr. Trump's 2017 Tax Cuts and Jobs Act, slated to sunset at year's end, seeking to make the cuts permanent in what has been a key priority for Senate Republicans. —Kaia Hubbard, CBS News, 28 June 2025

Without a clear plan to sunset aging systems, companies end up with more than just tech debt. —Rohit Ayyagari, Forbes.com, 12 June 2025

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
• brevet
• 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