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hellacious

adjective

ˌhe-ˈlā-shəs How to pronounce hellacious (audio)
Definition of hellaciousnext
1
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
2
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
  1. intense
  2. difficult
  3. intensive
  4. challenging
  5. fierce
  6. tough
  7. ferocious
  8. rigorous
Adjective
  • Ukrainian officials are expecting another winter of intense Russian strikes on energy infrastructure, a tactic Moscow has employed each winter of the full-scale invasion in a bid to freeze the country into submission.
    — David Brennan, ABC News, 15 Sep. 2026
  • In his research for both projects, his mood boards filled up with references to periods of intense cultural flowering cut short—Weimar Germany, 1970s Iran, Cuba in the ’50s, and New York City before the AIDS crisis.
    — Sean Santiago, Architectural Digest, 15 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
  • The second cohort members are all to become part of the intensive acceleration phase that’s steered by the Cambridge Institute for Sustainability Leadership innovation team, with a concentration on pilot readiness.
    — Jennifer Weil, Footwear News, 17 Sep. 2026
  • The inaugural Hot Springs Documentary Film Festival Filmmaker Retreat, a four-day intensive program for filmmakers based in the Mid-South/South, held in partnership with Indie Media Arts South, launching October 10 – 13.
    — Matthew Carey, Deadline, 17 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
  • Warren Buffett’s Berkshire Hathaway owns BNSF, and the railroad is a fierce critic of Vena’s takeover bid for Norfolk Southern.
    — John Lippert, Chicago Tribune, 6 Sep. 2026
  • Aaron Donald, one of the fiercest pass rushers in NFL history, is coming out of retirement to rejoin the Rams in hopes of winning another Super Bowl title.
    — Los Angeles Times, Los Angeles Times, 6 Sep. 2026
Definition of fierce
Adjective
  • Because of the heat wave's dramatic effect on everyday life, Paris became a tough place to walk around in the sunshine.
    — ABC News, ABC News, 15 Sep. 2026
  • But Chipotle has been in a tough spot since Niccol departed in 2024, and even as Boatwright’s plan shows signs of momentum (same-store sales have begun to tick back up again), there are open questions about Chipotle’s strategic direction.
    — Rohan Goswami, semafor.com, 15 Sep. 2026
Definition of tough
Adjective
  • The relationship between Xi and Zhang went back decades, extending not just to their childhoods but all the way back to their fathers, who were comrades in arms in China’s ferocious civil war.
    — Jonathan A. Czin, The Atlantic, 14 Sep. 2026
  • The ferocious drummer Martin Chambers, with his knifey sideburns, completed the quartet.
    — Owen Gleiberman, Variety, 14 Sep. 2026
Definition of ferocious
Adjective
  • To classify a new fiber, the FTC requires its makers to demonstrate that the material is fundamentally different from existing fibers, established through a rigorous regulatory review.
    — Jennifer Bringle, Footwear News, 15 Sep. 2026
  • Success in the exam, one of the most rigorous standardized tests in the world, allows students to study at Korea’s top universities.
    — Lim Hui Jie,Miko Jang, CNBC, 15 Sep. 2026
Definition of rigorous

Browse Nearby Words

hell
hellacious
hell-bent
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Cite this Entry

“Hellacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hellacious. Accessed 19 Sep. 2026.

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