High Street I deserted (6)
I believe the answer is:
stoned
'high' is the definition.
(I've seen this before)
'street i deserted' is the wordplay.
'street' becomes 'st'.
'i' becomes 'one' (Roman numeral for one).
'deserted' becomes 'd'.
'st'+'one'+'d'='STONED'
(Other definitions for stoned that I've seen before include "Slangily drunk or attacked with rocks" , "attacked with missiles" , "High on drugs or alcohol" , "Plastered" , "with jewels" .)