emphasis If you say that you are flabbergasted, you are emphasizing that you are extremely surprised. Everybody was flabbergasted when I announced I was going to emigrate to Australia. extremely surprised or shocked (Perhaps from flabby + aghast (= shocked))
as if struck dumb with astonishment and surprise; "a circle of policement stood dumbfounded by her denial of having seen the accident"; "the flabbergasted aldermen were speechless"; "was thunderstruck by the news of his promotion"