College girl in charge of masterpiece (7)
I believe the answer is:
classic
'masterpiece' is the definition.
(I have seen 'Literary masterpiece ' mean 'classic' so perhaps 'masterpiece' could also mean 'classic')
'college girl in charge' is the wordplay.
'college' becomes 'c'.
'girl' becomes 'lass' (lass is a kind of girl**).
'in charge' becomes 'ic'.
'c'+'lass'+'ic'='CLASSIC'
'of' is the link.
(Other definitions for classic that I've seen before include "Artistic work of lasting excellence" , "Oaks perhaps" , "Remarkably typical" , "First-rate" , "Epsom Derby or St Leger Stakes, for example" .)