A few light smudges in colourless banner (5,4)
I believe the answer is:
white flag
'a few light smudges in' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
'colourless banner' is the wordplay.
'colourless' becomes 'white' (similar in meaning).
'banner' becomes 'flag' (I've seen this in another clue).
'white'+'flag'='WHITE FLAG'
Can you help me to learn more?
(Other definitions for white flag that I've seen before include "Sign of surrender" , "Symbol of truce" , "Pallid banner for surrender" , "Signal of truce or surrender" , "It signals surrender" .)