"Friends" star LeBlanc (4)
I believe the answer is:
matt
'friends star leblanc' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for matt that I've seen before include "Dull, lustreless" , "Telegraph cartoonist" , "Dull, not shiny" , "- Lucas (Little Britain)" , "(Of surface) dull" .)