Meaning:
Lit. “a cat’s music”, which can be used either to describe a very noisy and dissonant (or simply: poor) music or a noise that irritates you. You can hear/read it quite often to describe groups of people making noise not to let someone else speak or partygoers singing and breaking glasses on the streets.
The expression obviously stems from caterwaul waking Polish people at night, especially in March. Its origin being the same as that of German “Katzenjammer”, this Polish expression is not used to describe a hangover.
