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

Motion Applied brings experience from motorsport, where power electronics face rapid load changes and intense operating conditions.

— Aamir Khollam, Interesting Engineering, 2 Sep. 2026
As if this weren’t enough for one day, Venus will also make its debut in the secretive and smoldering sign of Scorpio, where the love planet trades light-hearted flirtation for something deeper and way more intense.

— Valerie Mesa, PEOPLE, 1 Sep. 2026

Definition of intense

Adjective

Being undefeated after a trio of difficult opening matches can only be seen as a positive, even if Newcastle’s obvious shortcomings require addressing if that run is to be prolonged.

— Chris Waugh, New York Times, 6 Sep. 2026
Engineers need flight data on propulsion, aerodynamics, thermal management, guidance and other subsystems under conditions that are difficult to reproduce on the ground.

— Bojan Stojkovski, Interesting Engineering, 6 Sep. 2026

Definition of difficult

Adjective

Saylor Hayes, 5, who was the subject of an intensive search involving hundreds of people and multiple agencies, was found in South Carolina on Sunday.

— Matt Lavietes, NBC news, 3 Sep. 2026
Authorities point to the Golden State’s intensive regulatory environment as a factor.

— Joel Mathis, TheWeek, 2 Sep. 2026

Definition of intensive

Adjective

Eric Loucks, the director of the Mindfulness Center at Brown, pointed out that a person can have a challenging experience during meditation and still find their overall meditation practice to be beneficial.

— Olga Khazan, The Atlantic, 4 Sep. 2026
For something more hands-on, Atlanta Motorsports Park in Dawsonville has a challenging kart circuit where karts can reach 50 mph or more.

— Chris Teague, AJC.com, 4 Sep. 2026

Definition of challenging

Adjective

Casemiro and Messi, fierce rivals when Casemiro was at Real Madrid and Messi at Barcelona, celebrated together, a rare sight for longtime La Liga fans.

— Michelle Kaufman, Miami Herald, 30 Aug. 2026
Pearce was celebrating five years of Opry membership and would return later to channel many aspects of Dolly, from her humor and fierce independence to her Appalachian roots.

— Chris Parton, USA Today, 30 Aug. 2026

Definition of fierce

Adjective

Space-grade electronics will cost more, and the ball’s shell—made from a material tough enough to roll over steel shards and withstand minus 184 °C temperatures—has never been evaluated in lunar extremes.

— IEEE Spectrum, IEEE Spectrum, 3 Sep. 2026
Democratic leaders face tough decisions on where to spend limited party resources to win the Senate majority.

— Burgess Everett, semafor.com, 3 Sep. 2026

Definition of tough

Adjective

That was the last time Tamang saw Yangri, who was whisked away by ferocious flash floods that ripped through this part of the Himalayan nation earlier this week.

— Sophie Tanno, CNN Money, 28 Aug. 2026
The run game of Agoura is ferocious and experienced, but Westlake’s QB play is better.

— Ethan Hanson, Daily News, 27 Aug. 2026

Definition of ferocious

Adjective

Seager's team is providing the AFN, along with their ongoing, rigorous science preparation.

— Leonard David, Space.com, 3 Sep. 2026
The 2022 Nature Biotechnology review urged rigorous clinical testing, and later reviews continued to flag reliability and standardization issues.

— Hanna Wickes, Charlotte Observer, 2 Sep. 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 6 Sep. 2026.

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Synonyms of hellacious

adjective

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