Beetle about in pubs coming back (6)
I believe the answer is:
scarab
'beetle' is the definition.
(scarab is a kind of beetle)
'about in pubs coming back' is the wordplay.
'about' becomes 'ca' (abbreviation for 'circa'**).
'in' is an insertion indicator.
'pubs' becomes 'bars' (I've seen this in other clues).
'coming back' shows that the letters should be reversed in order.
'bars' back-to-front is 'srab'.
'ca' inserted inside 'srab' is 'SCARAB'.
(Other definitions for scarab that I've seen before include "Old abuse" , "old lucky charm" , "Holy beetle" , "Sacred beetle of Eygpt" , "Large dark beetle" .)