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

Learning these smaller constellations helps fill in the gaps between the more obvious patterns. — Jamie Carter, Space.com, 24 July 2026 The English-language audio guide, included with your admission, fills in historical and cultural details. — Carolyn Heller, Forbes.com, 23 July 2026 See All Example Sentences for fill-in

Recent Examples of Synonyms for fill-in

Noun

Elgersma, a 22-year-old midfielder who starred at Redlands High, entered his second MLS match as a late substitute and ruined Roman Bürki’s clean sheet.

— Greg Beacham, Los Angeles Times, 23 July 2026
Moreover, topping up on certain vitamins is no substitute for a healthy, balanced diet.

— Cat Rainsford, Popular Science, 23 July 2026

Definition of substitute

Verb

Before Monday’s maneuver, the Russian ship informed HMS Tyne – a British patrol vessel – of its intention to conduct live-fire activity, CNN understands.

— Billy Stockwell, CNN Money, 21 July 2026
Both discoveries informed her choices for many of the principal cast and background actors.

— Sophia Panych, Allure, 20 July 2026

Definition of inform

Verb

Dutch Bros got its start in 1992 as a pushcart stand in Grants Pass, Oregon, according to the chain’s website.

— Emma Hall, Sacbee.com, 23 July 2026
So with the summit behind us and winter ahead, Europe stands in a more precarious position than most of its leaders are willing to say out loud.

— John Kerry, semafor.com, 23 July 2026

Definition of stand in

Noun

Those close to Villa say Rogers was worth 14 goals a season, so sourcing a replacement was critical.

— Chris Weatherspoon, New York Times, 22 July 2026
The Panthers had already moved to protect themselves on the left side, signing veteran tackle Rasheed Walker in March as a potential replacement for Ekwonu.

— Chantz Martin, FOXNews.com, 22 July 2026

Definition of replacement

Verb

The name traces back to farmers who hauled buckets, seed and equipment across their land before modern machinery took over.

— Hanna Wickes, Miami Herald, 24 July 2026
The move traces back to farmers hauling buckets, equipment or seed before modern machinery took over the work.

— Hanna Wickes, Fort Worth Star-Telegram, 24 July 2026

Definition of take over

Noun

The reliance on emergency actions, like diesel backup generators, incurs significant costs for ratepayers and increases air pollution.

— Anna Demeo, Forbes.com, 21 July 2026
With Hellebuyck leading the way and Skinner a luxury as a backup, the Jets will fight for a playoff spot and have cap space to make additions.

— Murat Ates, New York Times, 20 July 2026

Definition of backup

Verb

Varela noted that a different United representative had advised them by phone to arrive at SFO early Tuesday so airport customer service could fix the error.

— Thom Jensen, NBC news, 20 July 2026
For precaution, the weather service advises anyone spending time outdoors to know the symptoms of heat exhaustion, which include dizziness, thirst, nausea, heavy sweating and weakness.

— Ruth Abramovitz, Sun Sentinel, 20 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 27 Jul. 2026.

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Synonyms of fill-in

noun

verb

Example Sentences

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