Spiv with an off-target youth? (4,3)
I believe the answer is:
wide boy
'spiv' is the definition.
(I've seen this before)
'with an off-target youth?' is the wordplay.
'with' says to put letters next to each other.
'an off-target' becomes 'wide' (I've seen this in another clue).
'youth?' becomes 'boy' (male youth).
'wide' put next to 'boy' is 'WIDE-BOY'.
(Other definitions for wide boy that I've seen before include "petty young criminal" , "A rather unscrupulous person" , "Spiv" , "Tweedledum, for instance" .)