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
In the absence of his wife and regular cohost Kelly Ripa, the actor kicked off Thursday's Live edition by telling fill-in panelist Elle Duncan that he's severely bothered when, upon meeting a strapping fellow, the illusion of male bonding is shattered if their first handshake falls apart. EW.com, 7 Aug. 2025 Friday night, his fill-in, John Stamos, who had flown over from Spain, took the role anyway for a single night. Chris Willman, Variety, 4 Aug. 2025
Verb
Tools like Heimdall’s orb, dubbed the Neuron, can fill in that blank. IEEE Spectrum, 13 Aug. 2025 For this week’s Open Questions column, Cal Newport is filling in for Joshua Rothman. Cal Newport, New Yorker, 12 Aug. 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 20 Aug. 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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