hellacious

adjective

hel·​la·​cious ˌhe-ˈlā-shəs 

1

: exceptionally powerful or violent

hellacious winds

2

: remarkably good

has a hellacious curve ball

3

: extremely difficult

a hellacious climb

4

: extraordinarily large

a hellacious traffic jam

hellaciously adverb

Synonyms of hellacious

• intense
• intensive
• fierce
• ferocious
• terrible
• deep
• furious
• heavy

Examples of hellacious in a Sentence

Traffic is hellacious this time of day.

the hellacious heat was more than we could bear

Recent Examples on the Web

Wiggins was 99-101 with a hellacious slider and below-average command before he got hurt. — Keith Law, New York Times, 16 July 2026

The Hel Peninsula is one of Poland's busiest summer destinations, and getting there can be hellacious in peak vacation traffic. — Anna Noryskiewicz, CBS News, 1 June 2026

But the process of buying and selling homes at the same time seems hopelessly last-century – not to mention especially hellacious among all the difficult consumer experiences out there. — Andrea Riquier, USA Today, 28 May 2026

His hellacious brand of defense is a nightmare for opposing benches in particular. — Bryan Toporek, Forbes.com, 18 May 2026

Word History

Etymology

hell + -acious (as in audacious)

First Known Use

1929, in the meaning defined at sense 1

Rhymes for hellacious

• arenaceous
• argillaceous
• carbonaceous
• contumacious
• coriaceous
• efficacious
• farinaceous
• foliaceous
• membranaceous
• ochraceous
• olivaceous
• ostentatious