Clearly noticeable (6)
I believe the answer is:
marked
'clearly noticeable' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for marked that I've seen before include "Singled out; clearly noticeable" , "Pronounced" , "Easily noticeable" , "Read, corrected and awarded a grade" , "showing flag maybe" .)