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fill-in 1 of 2

noun

ˈfil-ˌin How to pronounce fill-in (audio)
Definition of fill-innext
as in substitute
a person or thing that takes the place of another I'm just a fill-in, so I have no idea where office supplies are kept

Synonyms & Similar Words

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fill in

2 of 2

verb

1
as in to inform
to give information to my friend quickly filled me in on the portion of the movie that I had missed

Synonyms & Similar Words

Antonyms & Near Antonyms
2
as in to substitute
to serve as a replacement usually for a time only she's only filling in while the regular secretary is on vacation

Synonyms & Similar Words

Example Sentences

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.
Recent Examples of fill-in
Noun
Based on the current fill-in rotation, Isola and Mina Kimes would be among the most plausible candidates. — Bobby Burack Outkick, FOXNews.com, 20 Aug. 2026 Gibbons, now 76, and Francis will continue to perform as ZZ Top and will resume the group’s postponed tour with a date in Austin, Texas this weekend with a fill-in drummer, a rep confirms to Variety. — Steven J. Horowitz, Variety, 18 Aug. 2026
Verb
And today’s LLMs are able to call on other computational modules to fill in their weak spots, so language is the gateway to ever-broader capacity. — George Musser, Scientific American, 17 Sep. 2026 With one cohost out (temporarily), iconic daytime series The View is bringing back multiple former cohosts to fill in at the Hot Topics table over the next few weeks. — Joey Nolfi, Entertainment Weekly, 17 Sep. 2026 See All Example Sentences for fill-in
Recent Examples of Synonyms for fill-in
  1. substitute
  2. inform
  3. stand in
  4. replacement
  5. tell
  6. take over
  7. backup
  8. advise
Noun
  • New cookbook releases and celebrity recipes that use cottage cheese as a ricotta or cream cheese substitute rather than a topping.
    — Ryan Brennan, Fort Worth Star-Telegram, 23 Sep. 2026
  • In July, the department accused UC San Diego’s medical school of using hardship questions as a substitute for directly considering race.
    — Jaweed Kaleem, Los Angeles Times, 23 Sep. 2026
Definition of substitute
Verb
  • Join more than 350,000 subscribers and keep yourself informed with a selection of The Week’s most interesting, enlightening and entertaining stories - plus daily puzzles.
    — Devika Rao, TheWeek, 22 Sep. 2026
  • The Hollingsworths are pulled closer together once they’re informed by Nia (Antoinette Crowe-Legacy), a detective with Homeland Security — hey, there’s one more square for your federal agency bingo card!
    — Angie Han, HollywoodReporter, 21 Sep. 2026
Definition of inform
Verb
  • But newspaper people ought to stand in solidarity with our broadcast brethren/competitors in this incredibly small-minded and grudging clash between the White House and the Washington press corps.
    — Arkansas Online, Arkansas Online, 23 Sep. 2026
  • The remarks stand in stark contrast to Trump’s earlier posture toward Greenland, which had included months of combative rhetoric, tariff threats and a refusal to rule out military force to acquire the island.
    — Alejandra Jaramillo, CNN Money, 22 Sep. 2026
Definition of stand in
Noun
  • Someone had to volunteer to cycle to the nearest village and cadge a replacement, fifteen kilometres each way, some of it on a narrow lane through tall hacks of dense grass.
    — Literary Hub, Literary Hub, 22 Sep. 2026
  • Nathan is happy to blame Joe for the fact that guest Michelle fully broke her shoulder while tubing and will need replacement surgery once back home.
    — Rafaela Bassili, Vulture, 22 Sep. 2026
Definition of replacement
Verb
  • When Arisa proclaims herself a Faithful, Michael looks hilariously stunned, and Alan tells them to weep for the fall of innocence and the failure of justice.
    — Alice Burton, Vulture, 25 Sep. 2026
  • Hawaii officials told residents to put together emergency kits and the governor issued an emergency proclamation, activating more than 230 Hawaii National Guard members.
    — MEGAN JANETSKY, Arkansas Online, 25 Sep. 2026
Definition of tell
Verb
  • Soon after starting college, Nussbaum joined students who took over the University of Chicago administration building.
    — Literary Hub, Literary Hub, 24 Sep. 2026
  • Then, sometime in the 2000s, a different Cruise took over, the star whose name alone could still fill a theater.
    — Clayton Davis, Variety, 23 Sep. 2026
Definition of take over
Noun
  • Part of the answer lies in building a resilience posture backed by more inventory, backup suppliers and better tracking and monitoring software.
    — Zaharia-Gabriel Sidere, Forbes.com, 21 Sep. 2026
  • In addition to playing lead guitar, Gilbert wrote songs and sang backup vocals.
    — Tracy Brown, Los Angeles Times, 21 Sep. 2026
Definition of backup
Verb
  • After washing, Adriano advises laying brushes flat or upside down to dry, with the bristles pointing downward.
    — Bianca Lambert, Southern Living, 21 Sep. 2026
  • Residents were advised to prepare to leave, gather important belongings and make arrangements for pets in case the warning was upgraded to an evacuation order.
    — Nicole Buss, Sacbee.com, 21 Sep. 2026
Definition of advise

Browse Nearby Words

fillies
fill-in
fill in
See all Nearby Words

Cite this Entry

“Fill-in.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fill-in. Accessed 26 Sep. 2026.

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