Experience release, securing some work (7)
I believe the answer is:
undergo
'experience' is the definition.
('undergo' can be a synonym of 'experience')
'release securing some work' is the wordplay.
'release' becomes 'undo' (I've seen this before**).
'securing' is an insertion indicator.
'some work' becomes 'erg' (an erg is a unit of work done).
'undo' going around 'erg' is 'UNDERGO'.
(Other definitions for undergo that I've seen before include "Withstand" , "Endure, experience something" , "Experience or live through" , "Suffer, experience" , "Suffer reverse" .)