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Synonyms

hellacious

American  
[he-ley-shuhs] / hɛˈleɪ ʃəs /
Or hellaceous

adjective

Slang.
  1. remarkable; astonishing.

    They're raising a hellacious amount of money in taxes.

  2. formidably difficult.

    We had a hellacious time getting here in the blizzard.


hellacious British  
/ hɛˈleɪʃəs /

adjective

  1. remarkable; horrifying

  2. wonderful; excellent

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of hellacious

hell + -acious (extracted from audacious, sagacious, vivacious, etc.), perhaps with intensive or augmentative force; bodacious, splendacious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Saban had turned another national stage into a disaster, a vast abyss of icy winds and hellacious fury.

From Los Angeles Times • Jan. 2, 2024

No matter which quarterback was under center, the Commanders had trouble stopping San Francisco’s hellacious front.

From Washington Times • Dec. 24, 2022

That hellacious blaze, which burned nearly 1,000,000 acres through five counties for more than three months, was the largest single wildfire in California history.

From Seattle Times • Sep. 16, 2022

She was among the sport’s elites seven years ago, a rising star whose hellacious power and risk-it-all tactics propelled her to the semifinals of the 2015 Australian Open at 19.

From Washington Post • Jan. 25, 2022

“We could be in for a hellacious event,” he said.

From "The Hot Zone" by Richard Preston