Brown who wrote "The Da Vinci Code" (3)
I believe the answer is:
dan
'brown who wrote the da vinci code' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for dan that I've seen before include "Judo level of proficiency (3)" , "degree of proficiency in judo, say?" , "Black-belt grade of proficiency" , "Karate expert" , "Person proficient in judo" .)