Group of words becomes ragged when spoken (6)
I believe the answer is:
phrase
'group of words' is the definition.
(I've seen this before)
'becomes ragged when spoken' is the wordplay.
'becomes ragged' becomes 'frays'.
'when spoken' indicates a 'sounds like' (homophone) clue.
'frays' sounds like 'PHRASE'.
(Other definitions for phrase that I've seen before include "Mode of expression" , "Group of words within a sentence" , "a certain expression" , "Sherpa (anag)" , "Group of words without a verb" .)