Lie about attitude (6)
I believe the answer is:
repose
'lie' is the definition.
(reposing is a kind of liing)
'about attitude' is the wordplay.
'about' becomes 're' (common abbreviation for 'with reference to').
'attitude' becomes 'pose' (I've seen this before).
're'+'pose'='REPOSE'
(Other definitions for repose that I've seen before include "Lie at rest" , "peace" , "State of tranquillity" , "calm" , "place" .)