HORRENDOUSLY
Scrabble letter values: H4O1R1R1E1N1D2O1U1S1L1Y4 = 19
Definition
HORRENDOUSLY is the adverb form of HORRENDOUS.
adjective HORRENDOUS: causing fear or dread or terror.
Synonyms of HORRENDOUS: awful, dire, direful, dread(a), dreaded, dreadful, fearful, fearsome