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

In her absence, season 1 cohosts Star Jones and Debbie Matenopoulos are set to return to the show as fill-in cohosts, alongside fellow ex-panelists Lisa Ling and cohost Sherri Shepherd. — Joey Nolfi, Entertainment Weekly, 17 Sep. 2026 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

Verb

Hossein Amini did another draft and Watkins filled in to direct. — Chris Gardner, HollywoodReporter, 16 Oct. 2026 Michael Nagle | Bloomberg | Getty Images Hello, this is Hui Jie writing from Singapore, filling in for Leonie Kidd. — Lim Hui Jie, CNBC, 16 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

The report stated the test was not aimed at any country or specific target, and that relevant governments were informed ahead of time.

— Muskan Bhatia, Interesting Engineering, 19 Oct. 2026
The mass sampling and real-time information gathering on prediction markets can extend their utility to informing business decisions, according to Zitzewitz.

— Sasha Rogelberg, Fortune, 19 Oct. 2026

Definition of inform

Noun

Mixing wand finish is oxidizing for mixing lacks replacement with stainless steel material.

— NWA Democrat-Gazette, Arkansas Online, 19 Oct. 2026
Ty Dieffenbach isn’t going anywhere Heading into his first start at the Power Four level, there was still talk from coach Bob Chesney that there was a battle for Iamaleava’s replacement between Dieffenbach and Madden Iamaleava.

— Connor Dullinger, Los Angeles Times, 19 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

Ohio State could still beat USC on the road, even with a backup, considering the Trojans' struggles to win big games under Riley and their suffocating defense.

— Ian Miller OutKick, FOXNews.com, 19 Oct. 2026
The team’s 2026 fortunes now rest in the hands of career backup Tanner McKee, a sixth-round 2023 draft pick.

— David K. Li, NBC news, 19 Oct. 2026

Definition of backup

Verb

Engineering textbooks advise practitioners to limit any settlement to around 1 to 3 inches, depending on the soil.

— Denise Hruby, Miami Herald, 19 Oct. 2026
In a social media post, police advised people nearby to stay alert, be aware of their surroundings and keep children and pets close.

— Nicole Buss, Sacbee.com, 19 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 20 Oct. 2026.

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Synonyms of fill-in

noun

verb

Example Sentences

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