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

In the summer, open-air cinema and theater performances take over an amphitheater on the edge of the lake, which makes for a stunning setting for watching the sunset. —Emily Manthei, Travel + Leisure, 19 July 2025

Additionally, the vibrant colors of sunrises and sunsets is an exercise in physics but is a natural process that proves Earth is not flat. —Marshall Shepherd, Forbes.com, 19 July 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

After July 1, 2026, there will be just two repayment programs for anyone who takes out new loans, while some plans for current borrowers will sunset in 2028. —Zachary Schermele, USA Today, 14 July 2025

Meanwhile, army bases in California, Arizona, Kansas, Oklahoma, and Texas will sunset their MWE programs. —Andrew Paul, Popular Science, 9 July 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