Terribly pleased -- passed! (7)
I believe the answer is:
elapsed
'passed' is the definition.
('elapse' can be a synonym of 'pass')
'terribly pleased' is the wordplay.
'terribly' is an anagram indicator.
'pleased' is an anagram of 'ELAPSED'.
(Other definitions for elapsed that I've seen before include "Pleased to have passed" , "Went by" , "Pleased (anag.)" , "Passed, of time" , "Expired" .)