Likely loner unpaired since turning up (5)
I believe the answer is:
saddo
'likely loner' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.
'unpaired since turning up' is the wordplay.
'unpaired' becomes 'odd' (synonyms).
'since' becomes 'as' (both can mean 'because').
'turning up' 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 "He's pathetic!" , "loser" , "lonely person" , "Boring loner" , "pathetic person" .)