DOUBTLESS Synonyms: 89 Similar and Opposite Words

doubtless 1 of 2

adjective

Definition of doubtless

as in sure

having or showing a mind free from doubt another one of his doubtless predictions that will never come true

Synonyms & Similar Words

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Antonyms & Near Antonyms

doubtless

2 of 2

adverb

ˈdau̇t-ləs

as in certainly

without any question she is doubtless the one and only girl for me

Synonyms & Similar Words

as in probably

by reasonable assumption doubtless you have heard this story before, but I'll tell it anyway

Synonyms & Similar Words

Antonyms & Near Antonyms

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 doubtless

Adjective

And the all-boffo, all-the-time production is exhausting (which is doubtless why the rare quiet moments stand out). — Bill Goodykoontz, The Arizona Republic, 29 Nov. 2022 Like Shannon, Natalie followed a circuitous musical path, dabbling in noise rock and once fronting a band called Satanized, doubtless to the delight of her Pentecostal parents. — Daniel De Visé, SPIN, 13 Sep. 2022

Adverb

But the show’s creatives have been looking to deftly expand Rowling’s beloved source material and will doubtless find some fresh ways to elevate the story. — James Hibberd, HollywoodReporter, 6 May 2026 Savings here and there are doubtless feasible. — Editorial, Boston Herald, 17 Apr. 2026 See All Example Sentences for doubtless

Recent Examples of Synonyms for doubtless

Adjective

While Kennedy isn't sure exactly how much of the liquid was used for the stage show, McRae's team did use 135 gallons for the gold bath video shown in the Lollapalooza visuals; Kennedy estimates the stage gold bath was about half that size.

— Kara Nesvig, Allure, 3 Aug. 2026
Just a few months ago, WWE fans weren’t sure that Owens would ever wrestle again.

— Blake Oestriecher, Forbes.com, 2 Aug. 2026

Definition of sure

Adverb

This would be a well-below-normal season, and certainly a welcome one for coastal residents in the United States from South Texas to Florida to Maine.

— Eric Berger, ArsTechnica, 5 Aug. 2026
Bringing in the Frenchman would certainly be a statement signing, and significantly boost an attacking line that is depleted following the exit of Mohamed Salah and the long-term loss of Hugo Ekitike to injury.

— Chris Weatherspoon, New York Times, 5 Aug. 2026

Definition of certainly

Adjective

In the long run, leaders are confident the 19 new boats will prove suitable replacements for the Ohios.

— Brad Lendon, CNN Money, 8 Aug. 2026
These signals, coupled with the Jassy masterclass, made the market feel more confident that capex from the spenders hasn't peaked yet, which is good for the vendors.

— Kevin Stankiewicz, CNBC, 7 Aug. 2026

Definition of confident

Adverb

While the Fathom will surely attract some Ford truck enthusiasts, its size, price point and electric powertrain all also likely bring in new buyers.

— Greg Migliore, Forbes.com, 6 Aug. 2026
Preventing the development of an Iranian nuclear weapon is surely a vital interest, and destroying Iran’s nuclear program is a clear objective that was plausibly attainable.

— KORI SCHAKE, Foreign Affairs, 6 Aug. 2026

Definition of surely

Adverb

Central Washington will likely see even stronger winds, with gusts up to 35 mph possible starting Friday.

— Mary Gilbert, CNN Money, 6 Aug. 2026
Other, more recent ownership groups in Atlanta, New York and Miami would likely be in favor as well, as would clubs like the LA Galaxy and New York Red Bulls.

— John Cassillo, Forbes.com, 5 Aug. 2026

Definition of likely

Adjective

Jayson has nine active players on assured Hall paths right now, with four more close.

— Chris Branch, New York Times, 24 July 2026
For those looking for an M390 folder that combines efficient cutting geometry with a fuller, more assured grip, Hornbill presents a compelling evolution of Titaner’s knife lineup.

— New Atlas, New Atlas, 21 July 2026

Definition of assured

Cite this Entry

Style

“Doubtless.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/doubtless. Accessed 10 Aug. 2026.

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Synonyms of doubtless

adjective

adverb

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