Cambridge college speaker's sentimental (9)
I believe the answer is:
magdalene
'cambridge college' is the definition.
'speaker's sentimental' is the wordplay.
'speaker's' shows a homophone (sound like).
'sentimental' becomes 'maudlin' ('maudlin' can be a synonym of 'sentimental').
'maudlin' sounds like 'MAGDALENE'.
(Other definitions for magdalene that I've seen before include "saintly woman" , "College" , "See 21" .)