expression, godan verb (-tsu)
discord arises; trouble brews
Idiomatic expression literally meaning 'waves and wind rise', used figuratively for discord or trouble arising in relationships or situations.
あの二人の間には、最近波風が立っているらしい。
It seems that discord has arisen between those two lately.
会議で波風が立たないように、慎重に発言した。
I spoke carefully so as not to cause trouble at the meeting.