fill-in

1 of 2

noun

ˈfil-ˌin How to pronounce fill-in (audio)
Synonyms of fill-innext
: someone or something that fills in
She performed well as the emergency fill-in.

fill in

2 of 2

verb

filled in; filling in; fills in

transitive verb

1
: to enrich (something, such as a design) with detail
2
: to give necessary or recently acquired information to
I'll fill you in

intransitive verb

: to fill a vacancy usually temporarily
Interns filled in for regular staffers.

Synonyms of fill-in

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Noun

Verb

See All Synonyms & Antonyms in Thesaurus

Examples of fill-in in a Sentence

Noun I'm just a fill-in, so I have no idea where office supplies are kept Verb my friend quickly filled me in on the portion of the movie that I had missed she's only filling in while the regular secretary is on vacation
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
The fill-in tackle on the right side, Joshua Ezeudu, allowed a team-high five pressures. — Sam McDowell, Kansas City Star, 26 Oct. 2026 The Falcons were 0-2 with Cooper Rush as the fill-in starter. — ABC News, 19 Oct. 2026
Verb
Kevin Korchinski, Chicago’s top pick in the 2022 draft, seventh overall, filled in and played his second game this season. — ABC News, 25 Oct. 2026 With Kahlil Benson continuing to fill in for Josh Simmons at left tackle, Joshua Ezeudu made the start at right tackle in place of Jaylon Moore, who was ruled out because of a concussion. — Kansas City Star, 25 Oct. 2026 See All Example Sentences for fill-in

Word History

First Known Use

Noun

1917, in the meaning defined above

Verb

1840, in the meaning defined at transitive sense 1

Time Traveler
The first known use of fill-in was in 1840

Rhymes for fill-in

See All Rhymes for fill-in

Browse Nearby Words

fillet weld
fill-in
fill in
See all Nearby Words

Cite this Entry

“Fill-in.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fill-in. Accessed 27 Oct. 2026.

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Kids Definition

fill in

verb
1
: to furnish with specified information
fill in an application
filled us in on the latest news
2
: to fill a vacancy usually temporarily : substitute
filled in during the emergency
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