Set off from famous college in time (8)
I believe the answer is:
detonate
'set off' is the definition.
('detonate' can be a synonym of 'set off')
'famous college in time' is the wordplay.
'famous college' becomes 'eton' (I've seen this before).
'in' indicates putting letters inside.
'time' becomes 'date' (date is a kind of time).
'eton' going inside 'date' is 'DETONATE'.
'from' is the link.
(Other definitions for detonate that I've seen before include "go off with a bang" , "Trigger" , "Blow up, explode" , "Cause to explode" , "Set off explosive device" .)