愕然(がくぜん)

がくぜん
taru-adjective, to-adverb
astonished; dumbfounded; stunned
formalemotion
1. astonished; dumbfounded; stunned
shocked and unable to react, usually in a negative way
その知(し)らせに愕然(がくぜん)とした。
I was dumbfounded by the news.
結果(けっか)を見(み)て愕然(がくぜん)とした。
I was stunned when I saw the results.
I was so shocked by my own mistake that I couldn't speak.

Usage

Almost always used with とする: 愕然(がくぜん)とする
愕然(がくぜん) implies shock at something unexpected and usually negative. It suggests being left speechless.

Related words