FORMIDABLE Synonyms: 162 Similar and Opposite Words

formidable

adjective

ˈfȯr-mə-də-bəl

Definition of formidable

as in terrifying

causing fear a formidable, irascible old man who frightened the neighborhood children

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in difficult

requiring considerable physical or mental effort running a marathon is a formidable undertaking

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 formidable Expenses for the fest were formidable — the beachside main event required fencing, flooring, stage builds, environmental mitigation, sanitation and more on a stretch of sand that had never hosted a comparable event. — Los Angeles Times, 20 Aug. 2026 But building a machine powerful enough to fulfill that promise remains a formidable challenge. — Ben Brubaker, Quanta Magazine, 19 Aug. 2026 Rodriguez, who shares many similarities with Salazar, may shape up to be a formidable opponent given his strong name recognition, said Gamarra, who lives in District 27. — Amanda Rosa, Miami Herald, 19 Aug. 2026 That's formidable growth in general, and especially at that scale. — Kevin Stankiewicz,jeff Marks, CNBC, 19 Aug. 2026 See All Example Sentences for formidable

Recent Examples of Synonyms for formidable

Adjective

Equally jubilant and terrifying, his size brings both John and Jim Ross to this mythic quality.

— Charlotte Observer, Charlotte Observer, 28 Aug. 2026
He is described as a terrifying figure but also one who is learned and devoted to Shiva.

— Charles Preston, Encyclopedia Britannica, 28 Aug. 2026

Definition of terrifying

Adjective

The losses linked to the demise of these groups are difficult to quantify, but participants and advocates say the impacts will reverberate across federal agencies for years.

— Katia Riddle, NPR, 29 Aug. 2026
Ground surveys can provide more detailed information at a particular site, but covering an entire subway corridor that way would be difficult.

— Rupendra Brahambhatt, Interesting Engineering, 29 Aug. 2026

Definition of difficult

Adjective

The Freedom 250 Grand Prix circuit has proved to be a treacherous one, and that was highlighted in a frightening crash involving a pair of drivers early in the race.

— Matt Reigle OutKick, FOXNews.com, 23 Aug. 2026
And because cognition is so closely tied to a person’s sense of competence and identity, those changes can be surprisingly frightening.

— Lauryn Higgins, Flow Space, 19 Aug. 2026

Definition of frightening

Adjective

For the healthcare providers in attendance, the party — which featured games and activities for the kids — is a chance to see the real-life impact of their often emotionally challenging work.

— Toria Sheffield, PEOPLE, 29 Aug. 2026
Because of the challenging terrain, the bridges are designed to be constructed without heavy machinery.

— Fatma Tanis, NPR, 29 Aug. 2026

Definition of challenging

Adjective

Not to mention that the shows debuted touring drummer Anika Nilles, taking on the scariest gig imaginable, as well as keyboardist Loren Gold, who expanded the band to a four-piece for the first time.

— Brian Hiatt, Rolling Stone, 23 Aug. 2026
In a scary scene at Gillette Stadium on Saturday, Philadelphia Eagles running back Ja’Quinden Jackson lay motionless on the field following the opening kickoff against the New England Patriots.

— Brooks Kubena, New York Times, 23 Aug. 2026

Definition of scary

Adjective

The war, and in particular Iran’s direct targeting of the Gulf, makes this approach a tough pill to swallow.

— Dina Esfandiary, Foreign Affairs, 27 Aug. 2026
The conversation shifted from tougher ordinances toward resource allocation and investing in third spaces, which are places outside of work, school or home.

— Charlotte Observer, Charlotte Observer, 27 Aug. 2026

Definition of tough

Adjective

But even without it, there seems to be some truth to the idea that if these teams were terrible businesses, they wouldn’t be sold for billions of dollars.

— Evan Drellich, New York Times, 26 Aug. 2026
Not by tightening the siege on Iran directly, but by tightening the siege on those who help this regime, this terrible dictatorship.

— Mustafa Qadri, CNN Money, 26 Aug. 2026

Definition of terrible

Adjective

Every personal finance review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of home loan products.

— Kelsey Neubauer, CNBC, 28 Aug. 2026
But alongside serious thinkers such as Rankine, Ta-Nehisi Coates, and Saidiya Hartman, less rigorous writers and ideas were also elevated.

— Charles Finch, The Atlantic, 28 Aug. 2026

Definition of rigorous

Browse Nearby Words

formidability

formidable

forming

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“Formidable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/formidable. Accessed 30 Aug. 2026.

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Synonyms of formidable

adjective

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