[aghast] adj [ME agast, fr. pp. of agasten to frighten, fr. a- (perfective prefix) + gasten to frighten--more at abide, gast] (13c): struck with terror, amazement, or horror: shocked
AGHAST
Meaning of AGHAST in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012