Blocker of TV (3)
I believe the answer is:
'blocker of tv' 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 "-- Dare, comic hero" , "Dark and damp." , "Man's name; judo grade" , "Grade level in judo" , "Judo level of proficiency (3)" .)