Heard hero in lounge (4)
I believe the answer is:
idle
'in lounge' is the definition.
(I've seen this before)
'heard hero' is the wordplay.
'heard' indicates a 'sounds like' (homophone) clue.
'hero' becomes 'idol' (I've seen this in another clue).
'idol' is a homophone of 'IDLE'.
(Other definitions for idle that I've seen before include "Avoiding work, lazy" , "Fruitless" , "Lied about doing nothing" , "Good-for-nothing" , "Tick over like engine" .)