Teens were up for a bribe (9)
I believe the answer is:
sweetener
'a bribe' is the definition.
(I've seen this before)
'teens were up' is the wordplay.
'up' indicates an anagram (letters get chucked up).
'teens'+'were'='teenswere'
'teenswere' with letters rearranged gives 'SWEETENER'.
'for' is the link.
(Other definitions for sweetener that I've seen before include "carrot" , "Something tart could do with this" , "Substance like sugar" , "Bribe (informal)" , "Bribe - sugar substitute" .)