Everyone into lousy tune (6)
I believe the answer is:
ballad
'tune' is the definition.
(type of song)
'everyone into lousy' is the wordplay.
'everyone' becomes 'all' (all people).
'into' indicates putting letters inside.
'lousy' becomes 'bad' (similar in meaning).
'all' placed into 'bad' is 'BALLAD'.
(Other definitions for ballad that I've seen before include "Slow romantic song" , "Narrative song of popular origin" , "delivered by singer" , "Poem telling a story" , "Narrative poem or song" .)