Uncouth people discussing why boobs wobble (6)
I believe the answer is:
yobbos
'uncouth people' is the definition.
(informal term for misbehaving youths)
'discussing why boobs wobble' is the wordplay.
'discussing' indicates a 'sounds like' (homophone) clue.
'wobble' indicates anagramming the letters (letters wobble around).
'why' sounds like 'y'.
'boobs' with letters rearranged gives 'obbos'.
'y'+'obbos'='YOBBOS'
(Other definitions for yobbos that I've seen before include "Young louts" , "Louts (colloq.)" , "Hooligans, ruffians" , "More than one tough" .)