ㄒㄧㄣˋxìnㄎㄡˇkǒu

  1. 不加思索任意發言·白居易故人讀書信口。」文明小史·》:花叢手舞足蹈不知如何是好海闊天空信口亂說。」

to blurt sth out, to open one's mouth without thinking