G0290400 (gro͞o′səm)adj. Causing horror and repugnance; frightful and shocking: a gruesome murder. See Synonyms at ghastly.[Obsolete grue, to shudder (from Middle English gruen, from Middle Dutch grūwen or Middle Low German gruwen) + -some.]grue′some·ly adv.grue′some·ness n.Thesaurus
Adv.
1.
gruesomely - in a gruesome manner; "he was gruesomely wounded"