Everybody, say, runs round pretty quickly (7)
I believe the answer is:
allegro
'quickly' is the definition.
(musical term)
'everybody say runs round' is the wordplay.
'everybody' becomes 'all' (all people).
'say' becomes 'eg' (both can mean 'for example').
'runs' becomes 'r' (cricket abbreviation).
'round' becomes 'o' (round can mean a round object).
'all'+'eg'+'r'+'o'='ALLEGRO'
'pretty' acts as a link.
This may not be correct. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for allegro that I've seen before include "Fast (mus.)" , "Instruction to perform in lively fashion" , "Scored at a brisk speed" , "Lively, quick (mus.)" , "Quickly (in music)" .)