Acquire drug on street, getting intense (7)
I believe the answer is:
earnest
'intense' is the definition.
(thesaurus)
'acquire drug on street' is the wordplay.
'acquire' becomes 'earn' (earning is a kind of acquiring).
'drug' becomes 'e' (E is another name for ecstasy).
'on' says to put letters next to each other.
'street' becomes 'st' (abbreviation).
'earn'+'e'+'st'='EARNEST'
'getting' is the link.
(Other definitions for earnest that I've seen before include "showing seriousness" , "Eastern (anag.)" , "Fervent - down payment" , "Sincere in intention" , "Solemn; pledge" .)