[ghast.ly] adj ghast.li.er ; -est [ME gastly, fr. gasten to terrify--more at gast] (14c) 1 a: terrifyingly horrible to the senses: frightening "a ~ crime" b: intensely unpleasant, disagreeable, or objectionable "such a life seems ~ in its emptiness and sterility --Aldous Huxley"
2: resembling a ghost 3 obs: filled with fear
4: very great "~ mistake" -- ghast.li.ness n -- ghastly adv syn ghastly, grisly, gruesome, macabre, lurid mean horrifying and repellent in appearance or aspect. ghastly suggests the terrifying aspects of corpses and ghosts "a ghastly accident". grisly and gruesome suggest additionally the results of extreme violence or cruelty "an unusually grisly murder" "the gruesome history of the Nazi death camps". macabre implies a morbid preoccupation with the physical aspects of death "a macabre tale of premature burial". lurid adds to gruesome the suggestion of shuddering fascination with violent death and esp. with murder "the lurid details of a crime".