The definition of aghast is someone or something who has been surprised, awed or horrified.(adjective)
An example of someone who might feel aghast is a person who returns home to find his house has burned down.
See aghast in Webster's New World College Dictionary
Origin: ME agast, pp. of agasten, to terrify < a-, intens. + gasten < OE gaestan, to terrify < gast, ghost
See aghast in American Heritage Dictionary 4
Origin: Middle English agast
Origin: , past participle of agasten, to frighten
Origin: : a-, intensive pref. (from Old English ā-)
Origin: + gasten, to frighten (from Old English gǣstan, from gāst, ghost).
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