FILL (IN) Synonyms: 79 Similar and Opposite Words

fill-in 1 of 2

noun

ˈfil-ˌin

Definition of fill-in

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

Relevance

fill in

2 of 2

verb

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

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

Okuayinonu, a fill-in starter the past two seasons, practiced Wednesday before a foot injury kept him from joining the 49ers on their charter flight here. — Cam Inman, Mercury News, 5 Sep. 2026 Before taking on her first solo anchoring role, Hylton frequently served as a fill-in anchor across the network’s morning, dayside and primetime programming. — Jill Goldsmith, Deadline, 31 Aug. 2026

Verb

Documentation has long been treated like a publishing task, which worked when the reader could fill in the gaps. — Han Wang, Fortune, 9 Oct. 2026 That strange acclimation extends to the human characters, whose emotional histories are gradually filled in. — Alison Foreman, IndieWire, 9 Oct. 2026 See All Example Sentences for fill-in

Recent Examples of Synonyms for fill-in

Noun

Liverpool coach Andoni Iraola dropped Virgil van Dijk to the substitutes’ bench with French defender Jérémy Jacquet starting.

— ABC News, ABC News, 14 Oct. 2026
But there’s no substitute, at the end of the day, for the human biologist.

— Adam Kovac, Scientific American, 14 Oct. 2026

Definition of substitute

Verb

His archival sketches of solitaire diamond rings also informed the design.

— Thomas Waller, Footwear News, 13 Oct. 2026
The facility lacks a verifiable method that informs food employees of their responsibility to report their health status in regards to illnesses that can spread through food.

— Arkansas Online, Arkansas Online, 12 Oct. 2026

Definition of inform

Noun

That includes construction, improvement, maintenance, repair and replacement of streets and sidewalks, as well as drainage, sewers and other related infrastructure.

— Nicole Buss, Sacbee.com, 12 Oct. 2026
The infrastructure work to create the tunnel, including road and drainage replacement, life safety systems and adding the structural elements, does not allow for separate lane closures, according to project information.

— Chris Higgins, Kansas City Star, 12 Oct. 2026

Definition of replacement

Verb

Some economists, including researchers at the Minneapolis Fed, argue the data don’t tell such a clean story.

— Molly A. Wallace, Fortune, 16 Oct. 2026
The company agrees with skeptics like the NFL that justices must eventually opine on whether states and tribes should regulate its sports event contracts as sports bets, a Supreme Court litigator working with Kalshi told Semafor.

— Eleanor Mueller, semafor.com, 16 Oct. 2026

Definition of tell

Verb

Two other pilots who happened to be traveling on the flight then took over and were able to safely land the plane at the airport in Riyadh, Saudi Arabia.

— Cynthia Littleton, Variety, 15 Oct. 2026
After Beidelman Furniture closed its doors in April, Ellsworth Partners took over the building where the 165-year-old furniture store sat at the corner of Jackson Avenue and Washington Street.

— Carolyn Stein, Chicago Tribune, 14 Oct. 2026

Definition of take over

Noun

For Morgan Stanley, investors will be watching strength in merger and acquisition advisory profits, as well as how the backup in bond yields that began in late August may affect lending, M & A activity and startup funding.

— Deena Zaidi, CNBC, 12 Oct. 2026
Hubbard has been carrying the weight of the run game pretty much by himself through four weeks; his usage wasn’t helped by the fact that backup running back Jonathon Brooks was placed on IR because of surgery to his core.

— Alex Zietlow, Charlotte Observer, 12 Oct. 2026

Definition of backup

Verb

Inside, Kaylee is eager to prove herself by really learning laundry and nailing it; Fraser advises her to come up with a system and stick to it.

— Rafaela Bassili, Vulture, 13 Oct. 2026
In recent history, the Justice Department's practice has been to advise prosecutors not to take any overt investigative steps against members of Congress or candidates within 60 days of an election.

— ABC News, ABC News, 12 Oct. 2026

Definition of advise

Browse Nearby Words

fillies

fill-in

fill in

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Cite this Entry

Style

“Fill-in.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fill-in. Accessed 17 Oct. 2026.

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Synonyms of fill-in

noun

verb

Example Sentences

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