Second refusal at college offers exclusive control (8)
I believe the answer is:
monopoly
'exclusive control' is the definition.
(I've seen this in another clue)
'second refusal at college' is the wordplay.
'second' becomes 'mo' (both are short periods of time).
'refusal' becomes 'no'.
'at' says to put letters next to each other.
'college' becomes 'poly' (polytechnic).
'mo'+'no'+'poly'='MONOPOLY'
'offers' is the link.
(Other definitions for monopoly that I've seen before include "Position of having no competitors" , "Exclusive (trade) control" , "No competition" , "Situation of one company's dominance in a particular market" , "Market in which there are many buyers but only one seller" .)