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

An unusually intense El Niño event is gathering strength in the tropical Pacific in a hurry.

— Andrew Freedman, CNN Money, 4 Aug. 2026
Thousands of Offers Nazareth University, located near Rochester, New York, is using direct admissions in part to reach those outside of the state where competition for students is particularly intense.

— Bloomberg, Mercury News, 4 Aug. 2026

Definition of intense

Adjective

For a long time, we’ve all been told that remastering the older Super Robot Wars games was extremely difficult, due to all the licensing and other costs involved.

— Ollie Barder, Forbes.com, 2 Aug. 2026
After three difficult years, armed groups loyal to Tehran appear to be bouncing back across the Middle East, reinforcing Iran’s leverage in its war with the US and Israel.

— Sophie Tanno, CNN Money, 2 Aug. 2026

Definition of difficult

Adjective

Both these ingredients are extremely energy intensive, raising concerns about energy demands if they are scaled in their current forms.

— Ameya Paleja, Interesting Engineering, 6 Aug. 2026
Companies are exploring off-planet storage, cloud-like computing, AI processing, data sovereignty and potentially power-intensive workloads in orbit.

— Ben Topor, Forbes.com, 6 Aug. 2026

Definition of intensive

Adjective

Even during a challenging season, Stanek continued to showcase one of baseball's hardest fastballs with a plus slider, splitter and sweeper.

— Peter Chawaga, Forbes.com, 1 Aug. 2026
There’s also 20-year-old Connor Zilisch, who’s had a challenging rookie season but is still one of the most prized young drivers to ever join the Cup Series.

— Alex Kirshner, New York Times, 1 Aug. 2026

Definition of challenging

Adjective

Management tried to modernize a restaurant brand built around nostalgia, underestimated how strongly customers identified with its image, and eventually reversed the change after a fierce backlash.

— Jim Osman, Forbes.com, 2 Aug. 2026
The jostling grew particularly fierce between South Carolina and Nevada.

— Los Angeles Times, Los Angeles Times, 2 Aug. 2026

Definition of fierce

Adjective

That left the debtor having to prove the negative that the debtor really didn't have any way to re-establish control over trust assets, and such was (and still is) a very tough sell.

— Jay Adkisson, Forbes.com, 7 Aug. 2026
Lombard also helped turn a double play in the second inning and handled another tough one-hopper hit by Cesar Prieto in the seventh.

— Peter Sblendorio, New York Daily News, 6 Aug. 2026

Definition of tough

Adjective

To the world, McRae is a strong, fearless entertainer, a triple threat who can pen songs that recall the fizzy pop of the early aughts and bring them to life as a ferocious singer and dancer.

— Steven J. Horowitz, Variety, 3 Aug. 2026
In 1970, Milton Friedman’s ferocious political essay in the New York Times, and the agency-theorizing that followed provided sufficient intellectual justification.

— Steve Denning, Forbes.com, 2 Aug. 2026

Definition of ferocious

Adjective

Academy leaders have repeatedly told Congress that rigorous scholarship, civilian faculty expertise and exposure to complex questions help prepare officers for the uncertainty of modern warfare.

— James LaPorta, CBS News, 31 July 2026
The progress marks the transition from years of design, research, and technology demonstrations to the construction of physical aircraft that will undergo rigorous testing before entering operational service.

— Prabhat Ranjan Mishra, Interesting Engineering, 31 July 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 7 Aug. 2026.

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Synonyms of hellacious

adjective

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