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

The coalition led by Prime Minister Pedro Sánchez's Socialists announced the new measures earlier Tuesday, after four days of intense protests centered around an encampment in Puerta del Sol, Madrid's most iconic plaza.

— Arkansas Online, Arkansas Online, 30 Sep. 2026
Consequently, the resulting economic stimulus, inflationary pressure, and intense competition for capital could propel the 10 year US Treasury yield toward a high of 6% before next January.

— , CNBC, 29 Sep. 2026

Definition of intense

Adjective

Finding people at high risk of incubating the Bundibugyo virus, also known as contact tracing, has proved difficult in Congo.

— CONSTANT SAME BAGALWA, Arkansas Online, 4 Oct. 2026
McKinsey’s data says some of those moves can be difficult for certain workers.

— Catherina Gioino, Fortune, 3 Oct. 2026

Definition of difficult

Adjective

At research-intensive institutions, critical knowledge is often distributed across specialized offices, sponsor websites, internal guidance, prior submissions and experienced staff.

— Mayank Kejriwal, Forbes.com, 1 Oct. 2026
Removing the thermal drying stage could also make electrode manufacturing less capital- and energy-intensive.

— Neetika Walter, Interesting Engineering, 1 Oct. 2026

Definition of intensive

Adjective

Until now, scientists could measure the total phosphorus preserved in ancient rocks, but determining the share that was actually available to marine life remained challenging.

— Sharmila Kuthunur, Space.com, 3 Oct. 2026
Alas, its path appears quite challenging, given that Digger earned a C+ CinemaScore from audiences and holds a 51 percent approval from reviewers on Rotten Tomatoes.

— Ryan Gajewski, HollywoodReporter, 3 Oct. 2026

Definition of challenging

Adjective

The rare show of alignment among fierce rivals was soon countered by comments from Meta’s Zuckerberg and Nvidia’s Jensen Huang, both of whom dismissed the slowdown idea.

— Alyson Shontell, Fortune, 5 Oct. 2026
The book and series focus on the complicated romance of Canadian hockey prodigy Shane Hollander (Hudson Williams) and Russian phenom Ilya Rozanov (Connor Storrie), who are the fierce on-ice rivals and the league’s best players.

— Nicole Fell, HollywoodReporter, 4 Oct. 2026

Definition of fierce

Adjective

With phones, keys, multi-tools, flashlights, water bottles and charging cables, the modern trouser and jacket pocket has a tough job coping.

— New Atlas, New Atlas, 29 Sep. 2026
Trump’s proclamation would have delayed compliance with the tougher standards from 2027 until 2029, though EPA ultimately repealed them in February.

— Luke Fountain, CNBC, 29 Sep. 2026

Definition of tough

Adjective

In the Atlantic, not a single hurricane has formed yet, a record for this late into hurricane season, due to ferocious wind shear brought on by El Niño.

— Sean Macaday, Sacbee.com, 5 Oct. 2026
When the Heat acquired Giannis Antetokounmpo in June, the natural instinct was to focus on the prodigious point production (57th all time), the volume rebounding (71st all time), the thunderous dunks and the ferocious forays to the basket.

— Barry Jackson, Miami Herald, 4 Oct. 2026

Definition of ferocious

Adjective

Operating-model transformation requires both strategic vision and rigorous accountability, and only finance leaders sit at the intersection of both.

— James Kavanaugh, Fortune, 30 Sep. 2026
Every personal finance article is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of personal finance and savings products.

— Jasmin Suknanan, CNBC, 30 Sep. 2026

Definition of rigorous

Browse Nearby Words

hell

hellacious

hell-bent

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Style

“Hellacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hellacious. Accessed 7 Oct. 2026.

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Synonyms of hellacious

adjective

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