Toady Conservative lord's back (5)
I believe the answer is:
creep
'toady' is the definition.
(thesaurus)
'conservative lord's back' is the wordplay.
'conservative' becomes 'c' (abbreviation commonly used in UK politics).
'lord' becomes 'peer' (peer is a kind of lord).
'back' is a reversal indicator.
'peer' reversed gives 'reep'.
'c'+'reep'='CREEP'
(Other definitions for creep that I've seen before include "snake" , "Of plants, to grow along the ground" , "Inch" , "Tiptoe" , "Walk slowly, silently" .)