Blue revolutionary left lodge (5)
I believe the answer is:
dwell
'lodge' is the definition.
(both can mean to inhabit a place)
'blue revolutionary left' is the wordplay.
'blue' becomes 'lewd' (both can mean vulgar or obscene).
'revolutionary' says the letters should be written in reverse.
'left' becomes 'l' (common abbreviation).
'lewd' back-to-front is 'dwel'.
'dwel'+'l'='DWELL'
(Other definitions for dwell that I've seen before include "Harp" , "Live (in a place)" , "Think moodily (on something)" , "Abide, reside" , "Lodge" .)