long face; looking dejected
Describes a facial expression that shows unhappiness, worry, or disappointment. Often used in set phrases like 浮かぬ顔をしている.
See also: 浮く
彼は浮かぬ顔で会議に参加した。
He attended the meeting with a long face.
浮かぬ顔をしているけど、何かあったの？
You look down. Did something happen?
Kana spelling is common in informal writing or when the kanji is considered less important.
From 浮かぬ (negative of 浮く, 'to be cheerful') + 顔 ('face'). The expression is a fixed phrase meaning 'a gloomy face'.