開あいた口くちがふさがらない

あ

い

た

く

ち

が

ふ

さ

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ら

な

い

Meanings

1

expression, i-adjective

dumbfounded; speechless; flabbergasted

idiomatic expression

Idiomatic expression describing a state of being so surprised or shocked that one's mouth hangs open and one cannot speak.

彼かれの突とつ然ぜんの告こく白はくに、開あいた口くちがふさがらなかった。
I was left speechless by his sudden confession.

そのニュースを聞きいて、開あいた口くちがふさがらない思おもいだった。

When I heard the news, I was utterly dumbfounded.

Written forms

開あいた口くちがふさがらない
Standard kanji-kana mixed spelling.
開あいた口くちが塞ふさがらない
Uses the less common kanji 塞 for ふさがる.

Kanji

開open, unfold, unseal
口mouth
塞close, shut, cover

Similar words

呆然ぼうぜん
呆然 is a more general state of being stunned or dazed, while 開いた口がふさがらない specifically emphasizes the physical reaction of being so surprised that one's mouth hangs open.
言こと葉ばを失うしなう
言葉を失う means 'to be at a loss for words' and is similar in meaning, but 開いた口がふさがらない is more vivid and colloquial, focusing on the visual image of an open mouth.

Etymology

Literally 'an opened mouth does not close'. The phrase is a vivid idiomatic expression describing the physical reaction of being so surprised that one's mouth remains agape.