Want ecstasy in retro joint (4)
I believe the answer is:
need
'want' is the definition.
(needing is a kind of wanting)
'ecstasy in retro joint' is the wordplay.
'ecstasy' becomes 'E' (informal term for the drug).
'in' means one lot of letters goes inside another.
'retro' says the letters should be written backwards (retro is Latin for 'backwards').
'joint' becomes 'den' (I am not sure about this - if you are sure you should believe this answer much more).
'den' in reverse letter order is 'ned'.
'e' going within 'ned' is 'NEED'.
Can you help me to learn more?
(Other definitions for need that I've seen before include "state of distress" , "must have results!" , "Rely on" , "state requiring relief" , "Want - require(ment)" .)