Hellaciously rhymes with:
fallaciously, fallaciously, graciously, ostentatiously, tenaciously, ambitiously, anxiously, cautiously, consciously, expeditiously, facetiously, fallaciously, graciously, ostentatiously, subconsciously, surreptitiously, suspiciously, tenaciously, unconsciously, viciously
Hellaciously sounds like:
halsell, helical, helsel, helsley, hoelzel, holsclaw