Mathematician gets Dulcie confused (6)
I believe the answer is:
euclid
'mathematician' is the definition.
(Euclid is an example)
'dulcie confused' is the wordplay.
'confused' indicates anagramming the letters.
'dulcie' anagrammed gives 'EUCLID'.
'gets' is the link.
(Other definitions for euclid that I've seen before include "Greek philosopher" , "Great Greek master of geometry" , "Ancient Greek mathematician" , "Alexandrian mathematician" , "Old Greek master of geometry" .)