Bit of perjury (3)
I believe the answer is:
lie
'bit of perjury' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for lie that I've seen before include "Assume a horizontal position" , "Prevaricate or recline" , "Stretch out" , "Recline - untruth" , "Couch" .)