Piano trio meet regularly playing with proper rhythm (6)
I believe the answer is:
intime
'playing with proper rhythm' is the definition.
I can't judge whether this defines the answer.
'piano trio meet regularly' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'piano'+'trio'+'meet'='pianotriomeet'
The alternating letters of 'pianotriomeet' are 'INTIME'.
Can you help me to learn more?
(Other definitions for intime that I've seen before include "Eventually, sooner or later" , "Early enough" , "Eventually or not late" , "'A stitch .. .... saves nine'" .)