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

Example Sentences

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
In each case, a reporter gleaned as much information from the records as possible to answer as many of the questions as possible, then verified its accuracy with the school and asked officials to fill in any gaps. USA Today, 16 Nov. 2022 Corden was scheduled to host his show on the night of her birth, but asked friend Harry Styles to fill in at the last minute. Jacqueline Weiss, Peoplemag, 19 Oct. 2022 Then-teammate Pyper Friedman, now a sophomore midfielder at William & Mary, asked Borzymowski to fill in at goalkeeper for the middle school team, and the latter gave up dancing shortly afterward. Edward Lee, Baltimore Sun, 7 Oct. 2022 When Loden worked in AT&T’s HR department, she was asked to fill in for a female manager at the 1978 Women’s Action Alliance Conference, the Post reported. Scottie Andrew, CNN, 6 Sep. 2022 How long Cairo will be asked to fill in is unknown. Paul Sullivan, Chicago Tribune, 31 Aug. 2022 When Cook was quarantined and unavailable for three games in mid-December, Rogers was asked to fill in, leading the Arabians to two victories, including a 50-42 win at Fishers. Brian Haenchen, The Indianapolis Star, 10 May 2022 One night in 1955, when the station’s overnight D.J. did not show up, Mr. Mark was asked to fill in. New York Times, 26 Apr. 2022 Jane Harper, a colleague of Jenkins’s, said on Twitter that Jenkins was scheduled to work Saturday, and Harper was asked to fill in when editors couldn’t reach Jenkins. Washington Post, 19 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fill-in.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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 7 Dec. 2022.

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
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