Rhythmic flow (7)
I believe the answer is:
cadence
'rhythmic flow' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for cadence that I've seen before include "Modulation of the voice" , "Vocal modulation or inflection" , "Lilt" , "Rhythm of the voice" , "Rise and fall" .)