Note worn-out shade (5)
I believe the answer is:
brown
'shade' is the definition.
(I've seen this before)
'note worn-out' is the wordplay.
'note' becomes 'b' (musical note).
'out' is an anagram indicator (out can mean wrong or inaccurate).
'worn' anagrammed gives 'rown'.
'b'+'rown'='BROWN'
(Other definitions for brown that I've seen before include "Four-point ball" , "Suntanned; sort of bear/study" , "cook to a rich colour?" , "After half portion of bran, have" , "Former PM" .)