Prevaricator’s return makes us complain vehemently (4)
I believe the answer is:
rail
'complain vehemently' is the definition.
(I've seen this before)
'prevaricator's return' is the wordplay.
'prevaricator' becomes 'liar' (synonyms).
'return' is a reversal indicator.
'liar' in reverse letter order is 'RAIL'.
'makes us' acts as a link.
(Other definitions for rail that I've seen before include "Track for wheels" , "transport system" , "Supported bar - inveigh" , "Form of transport" , "Bar - marsh bird" .)