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

Relevance

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

The problem, Snegovaya said, is that achieving military autonomy for Europe and Ukraine is extremely difficult in the short term, and Europe has been slow to develop the necessary capabilities.

— Elsa Ohlen, CNBC, 17 Oct. 2026
Past changes have pushed the glacier into a retreat that may be difficult to reverse, while new modeling suggests scientists may have underestimated how warm seawater reaches beneath it.

— Kaif Shaikh, Interesting Engineering, 17 Oct. 2026

Definition of difficult

Adjective

Atrium is also offering day hospital programs in which patients receive intensive treatment and return home at night.

— Charlotte Observer, Charlotte Observer, 15 Oct. 2026
Because schools would otherwise use that money to buy equipment, the proposal would most affect two-year technical schools with equipment-intensive programs like welding or automotive programs.

— CBS News, CBS News, 14 Oct. 2026

Definition of intensive

Adjective

As Hispanic Heritage Month continues, one musician at Philadelphia's Curtis Institute of Music is challenging expectations about classical music and the harp.

— Madeleine Wright, CBS News, 16 Oct. 2026
Naomi Ackie, who plays the scientist charged with Hagen’s experimental procedure, praised how her co-star shouldered what was a very challenging role.

— Chris Gardner, HollywoodReporter, 16 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 22 Oct. 2026.

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Synonyms of hellacious

adjective

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