fill-in

1 of 2

noun

: someone or something that fills 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

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
Together, the fill-in bosses turned an early one-score deficit into a 38-0 surge before obliterating Michigan State 38-13 on Saturday. Ira Gorawara, New York Times, 11 Oct. 2025 With right tackle Taylor Moton (elbow) ruled out for the game, Walton will back up fill-in starter Yosh Nijman at right tackle. Mike Kaye, Charlotte Observer, 11 Oct. 2025
Verb
And a lot of the pseudepigrapha, like the fake gospels and fake apocalypses, fill in gaps in the record that can serve latter-day, post-biblical purposes. JSTOR Daily, 16 Oct. 2025 Parade has tried to fill in some of the blanks. Lisa Respers France, CNN Money, 16 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Fill-in.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fill-in. Accessed 18 Oct. 2025.

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
Last Updated: - Updated example sentences
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