HELLACIOUS Synonyms: 154 Similar and Opposite Words

hellacious

adjective

ˌhe-ˈlā-shəs

Definition of hellacious

as in intense

extreme in degree, power, or effect the hellacious heat was more than we could bear

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in difficult

requiring considerable physical or mental effort the pioneers survived a particularly hellacious river crossing with their covered wagon barely in one piece

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 hellacious His hellacious brand of defense is a nightmare for opposing benches in particular. — Bryan Toporek, Forbes.com, 18 May 2026 The skiers were in a valley below Perry Peak, but the two survivors have described battling through hellacious conditions in the hour before the avalanche. — Andrew Graham april 2, Sacbee.com, 2 Apr. 2026 But the tour was a hellacious time for Bachman. — Andy Greene, Rolling Stone, 28 Feb. 2026 Even against a hellacious Houston defense, the Patriots’ shortest path to victory is to ask Maye to carry them yet again. — Andrew Callahan, Boston Herald, 15 Jan. 2026 See All Example Sentences for hellacious

Recent Examples of Synonyms for hellacious

Adjective

George Bonanno, a psychologist at Columbia University, explains that many people who have intense symptoms initially—such as nightmares and flashbacks—won’t develop PTSD.

— Maia Szalavitz, Scientific American, 20 Oct. 2026
Still, the competition among jewelers is becoming more intense, not only for sports team’s commissions but also to design ever flashier pieces with intricate details.

— Sara Germano, Sportico.com, 20 Oct. 2026

Definition of intense

Adjective

Jarman, who came in as the defending champion on the event, put together a more difficult routine but was nicked by judges for his execution.

— ABC News, ABC News, 24 Oct. 2026
This is the last remaining game on the schedule that should be very difficult.

— David Troy OutKick, FOXNews.com, 24 Oct. 2026

Definition of difficult

Adjective

Just a half-hour north of San Diego, the property is comprised of over 600 acres of hills, meadows, Japanese gardens, and citrus groves, including 30 miles of private hiking trails and five acres of bio-intensive gardens.

— Condé Nast, Condé Nast Traveler, 22 Oct. 2026
On the cost side, Zuckerberg did acknowledge that Muse is currently very compute-intensive.

— Zev Fima, CNBC, 22 Oct. 2026

Definition of intensive

Adjective

Such calculations are part of a wider effort to understand why molecular simulations remain challenging.

— Rupendra Brahambhatt, Interesting Engineering, 24 Oct. 2026
But the shift in college athletics has required an internal reconciling that is even more challenging than the external education.

— Dana O’Neil, CNN Money, 24 Oct. 2026

Definition of challenging

Adjective

His successor, Bennett, had been among its fiercest critics, raising the prospect that the arrangement might finally end.

— Eric Cortellessa, Time, 18 Oct. 2026
The deadly fire erupted Saturday at Canadian Forces Base Wainwright, where fierce winds fueled flames that spread beyond the installation and into surrounding rural areas.

— Stephen Sorace, FOXNews.com, 18 Oct. 2026

Definition of fierce

Adjective

The case has led to calls for tougher oversight of churches and other religious organizations in a country where religious faith plays a prominent role in public life.

— Jefferson Kahinju Reuters, Arkansas Online, 20 Oct. 2026
Thermal equilibrium might sound like a tough concept, but hundreds of systems reach them around us on a daily basis.

— Ameya Paleja, Interesting Engineering, 20 Oct. 2026

Definition of tough

Adjective

After the initial blast, which spews out gamma rays, a storm of radiation pours into the surrounding galaxy, creating a ferocious afterglow that burns in every part of the electromagnetic spectrum.

— Robin George Andrews, Scientific American, 20 Oct. 2026
The characters thrust and parry with ferocious wit in an upscale California desert setting that scenic designer Scott Pask generically satirizes as a category of social living.

— Theater Critic, Los Angeles Times, 19 Oct. 2026

Definition of ferocious

Adjective

Like SpaceX and Tesla CEO Elon Musk, many founders in tech have moonshot performance pay packages, in which rigorous stock price growth is tied to massive pay hurdles.

— Amanda Gerut, Fortune, 21 Oct. 2026
Every travel story is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of travel products.

— Liz Knueven, CNBC, 21 Oct. 2026

Definition of rigorous

Browse Nearby Words

hell

hellacious

hell-bent

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“Hellacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hellacious. Accessed 25 Oct. 2026.

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Synonyms of hellacious

adjective

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