Unwanted, like returning drip (5)
I believe the answer is:
saddo
'drip' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'unwanted like returning' is the wordplay.
'unwanted' becomes 'odd' (I can't justify this - if you can you should give a lot more credence to this answer).
'like' becomes 'as'.
'returning' is a reversal indicator.
'odd'+'as'='oddas'
'oddas' reversed gives 'SADDO'.
Can you help me to learn more?
(Other definitions for saddo that I've seen before include "loser" , "He's pathetic!" , "pathetic person" , "Boring loner" , "nerdy type" .)