Unfortunately rises track pay (6)
I believe the answer is:
salary
'pay' is the definition.
(I know that pay can be written as salary)
'unfortunately rises track' is the wordplay.
'unfortunately' becomes 'alas' ('alas' is used to express regret).
'rises' shows that the letters should be reversed in order.
'track' becomes 'RY' (abbreviation for railway).
'alas' written backwards gives 'sala'.
'sala'+'ry'='SALARY'
(Other definitions for salary that I've seen before include "Regular monthly wage" , "Regular earnings" , "Annual pay" , "Stipend" , "Monthly pay" .)