1 of 2


: someone or something that fills in

fill in

2 of 2


filled in; filling in; fills in

transitive verb

: to enrich (something, such as a design) with detail
: 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
After all, multiple players ahead of him on the depth chart were injured, and others who had received fill-in opportunities did little with them. Daniel Sperry, Kansas City Star, 3 May 2024 The laser instrument appeared to serve as a suitable fill-in, and everything appeared to be working until the spacecraft went silent for several minutes. Kenneth Chang, New York Times, 22 Feb. 2024 See all Example Sentences for fill-in 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fill-in.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use


1917, in the meaning defined above


1840, in the meaning defined at transitive sense 1

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

Dictionary Entries Near fill-in

Cite this Entry

“Fill-in.” Dictionary, Merriam-Webster, Accessed 18 May. 2024.

Kids Definition

fill in

: to furnish with specified information
fill in an application
filled us in on the latest news
: to fill a vacancy usually temporarily : substitute
filled in during the emergency
Last Updated: - Updated example sentences
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