Talk about lid (4)
I believe the answer is:
chat
'talk' is the definition.
(thesaurus)
'about lid' is the wordplay.
'about' becomes 'c' (abbreviation for 'circa').
'lid' becomes 'hat' ('hat' can be a synonym of 'lid'**).
'c'+'hat'='CHAT'
(Other definitions for chat that I've seen before include "Exchange text or voice messages through a computer" , "Talk informally; bird" , "Gossip" , "Talk familiarly" , "Casual conversation" .)