みみがはやい
being quick-eared; having sharp ears; being first to know about something
Also written 耳が速い、耳がはやい
Expression
彼かれは耳みみが早はやい。
He's in the know.
武田夫人ふじんは近所きんじょの噂うわさには耳みみが早はやい。
Mrs Takeda is quick to pick up on the local rumours.