The definition of ghastly is something repellent, horrible, frightful, ugly, macabre or sickly.(adjective)
See ghastly in Webster's New World College Dictionary
See ghastly in American Heritage Dictionary 4
adjective ghast·li·er, ghast·li·est
Origin: Alteration (influenced by ghost)
Origin: of Middle English gastli
Origin: , from gasten, to terrify; see aghast.
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