hellacious
adj/hɛˈleɪʃəs/
Etymology Unclear origins; perhaps from hell + -acious
1
horrible, awful, hellish, agonizing, difficult.
- Because he throws so many hellacious punches, he has the chance of knocking out any fighter on any given night.2007, Dan Horgan, Bringing Back Boxing: A Young Journalist's Attempt to Revive the Sweet Science, page 86:
2
nasty, repellent.
3
Slang Remarkable, unbelievable, unusual.
- Derived terms
- hellaciously, hellaciousness