Synonyms for Ghastly (same or very similar meaning)
WordNet sense 1 (gruesomely indicative of death or the dead):
sepulchral, charnelWordNet sense 2 (unpleasant or disgusting especially to the senses):
offensiveWordNet sense 3 (shockingly repellent; inspiring horror):
grim, grisly, gruesome, macabre, sickWordNet sense 4 (causing alarm or fear):
alarmingFrom the ODE community, based on WordNetadd/edit