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

Her cohost, Craig Melvin, and fill-in anchor, Sheinelle Jones, then revealed more details on her whereabouts at the top of Thursday's show. — Leigh Blickley, Entertainment Weekly, 18 June 2026 Injury fill-in Jovo Lukic headed in a corner kick in the 21st minute for Bosnia-Herzegovina, which is making its second World Cup appearance after failing to advance out of group play in 2014. — John Wawrow, Hartford Courant, 12 June 2026

Verb

Speaking with Goldman Sachs’s Raj Mahajan at the firm’s Apex Symposium on June 2 — audio Fortune has exclusive, embargoed access to — Griffin filled in the blanks. — Nick Lichtenberg, Fortune, 9 July 2026 Couric then handed the virtual mic to Molner, who filled in some of his wife’s blanks. — Theresa Braine, New York Daily News, 9 July 2026 See All Example Sentences for fill-in

Recent Examples of Synonyms for fill-in

Noun

The organizations getting beyond experimentation are redesigning their workflows around collaboration between AI and humans, rather than viewing one as a substitute for the other.

— Tony Bates, Fortune, 16 July 2026
In response, Paramount argued that the Paramount and WBD cable lineups are complementary — and not market substitutes — and that cable providers will still want access to all of the channels.

— Gene Maddaus, Variety, 16 July 2026

Definition of substitute

Verb

In addition,18 employees who had been placed in the 2026 fiscal year layoff prevention pool will be informed that their stay in that pool has expired, the district said.

— Jeramie Bizzle, CBS News, 14 July 2026
Prioritize safety, stay impeccably informed, and assume responsibility to shield lives and property.

— CA Weather Bot, Sacbee.com, 14 July 2026

Definition of inform

Verb

Moments later the Tesla Model 3 raced down a residential street in Katy, Texas, at highway speeds, slammed into a brick home and killed a 76-year-old woman standing in the front room.

— Bernard Condon, Fortune, 16 July 2026
But the Ukrainians are still confidently inside the town center, with the General Staff posting a video of one officer casually standing in Victory Square in November.

— Nick Paton Walsh, CNN Money, 16 July 2026

Definition of stand in

Noun

Margarita Betancourt, the district’s treasurer, is set to be appointed as Steiger’s replacement on an interim basis.

— Austin Horn July 15, Miami Herald, 15 July 2026
That approach could ease the transition to the new interceptor without requiring a complete replacement of supporting equipment.

— Aamir Khollam, Interesting Engineering, 15 July 2026

Definition of replacement

Verb

The deal is expected to be completed next summer, when the Morrison YMCA at 9405 Bryant Farms Road in Ballantyne would close and Moments of Hope would take over.

— Charlotte Observer, Charlotte Observer, 10 July 2026
This family-run collection of hotels began in the 1960s when an Italian businessman took over a stunning property in Porto Ercole, previously a hangout for international socialites.

— Megan Rose Murray, Condé Nast Traveler, 10 July 2026

Definition of take over

Noun

Always carry a physical guidebook or printed hike details in a waterproof bag as a backup, since batteries die and cell coverage on remote trails is often nonexistent.

— Hanna Wickes, Fort Worth Star-Telegram, 13 July 2026
The Jackson County Sheriff’s Office and the Missouri State Highway Patrol were called in for backup.

— Nathan Pilling, Kansas City Star, 13 July 2026

Definition of backup

Verb

To minimize risks during outdoor work, the Occupational Safety and Health Administration (OSHA) advises incorporating frequent rest breaks in shaded or air-conditioned areas.

— CA Weather Bot, Sacbee.com, 14 July 2026
The National Park Service advises visitors to stay at least 25 yards away from bison at all times and to never approach the animals.

— Sara Smart, CNN Money, 13 July 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 18 Jul. 2026.

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Synonyms of fill-in

noun

verb

Example Sentences

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