Laugh about women’s idle talk (7)
I believe the answer is:
'idle talk' is the definition.
'laugh about women's' is the wordplay.
'laugh' becomes 'titter' (titter is a kind of laugh**).
'about' is an insertion indicator.
'women' becomes 'w'.
'titter' going around 'w' is 'TWITTER'.
(Other definitions for twitter that I've seen before include "limited communications network" , "Sound made by bird" , "Talk excitedly" , "(Make) a noise like a bird" , "Chatter" .)