University teacher admitting new choice is not fully explored (9)
I believe the answer is:
unplumbed
'not fully explored' is the definition.
The answer and definition are different parts of speech. However, adjectives and past participle verbs occasionally define each other.
'university teacher admitting new choice' is the wordplay.
'university' becomes 'U' (abbreviation as in UMass).
'teacher' becomes 'BEd' (Bachelor of Education).
'admitting' indicates putting letters inside (admit can mean to welcome in or accept).
'new' becomes 'n' (abbreviation as in New Testament NT).
'choice' becomes 'plum' (both can mean excellent).
'u'+'bed'='ubed'
'n'+'plum'='nplum'
'ubed' placed around 'nplum' is 'UNPLUMBED'.
'is' is the link.
Can you help me to learn more?
(Other definitions for unplumbed that I've seen before include "missing pipes?" , "Too deep to have been measured" .)