Left streetwise kid finally rocking and rolling (8)
I believe the answer is:
lurching
'rolling' is the definition.
(thesaurus)
'left streetwise kid finally rocking' is the wordplay.
'left' becomes 'l' (common abbreviation).
'streetwise kid' becomes 'urchin' (child living on the street).
'finally' indicates one should take the final letters.
The last letter of 'rocking' is 'g'.
'l'+'urchin'+'g'='LURCHING'
'and' acts as a link.
(Other definitions for lurching that I've seen before include "Moving slowly and unsteadily" , "staggering unsteadily" .)