Quietly share out some sentence (6)
I believe the answer is:
phrase
'some sentence' is the definition.
(I have seen 'partial sentence' mean 'phrase' so perhaps 'sentence' could also mean 'phrase')
'quietly share out' is the wordplay.
'quietly' becomes 'p' (p for piano and quiet).
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'share' with letters rearranged gives 'hrase'.
'p'+'hrase'='PHRASE'
(Other definitions for phrase that I've seen before include "a certain expression" , "Short, coherent group of words" , "Group of words forming part of a sentence" , "Seraph (anag.)" , "partial sentence" .)