Polite young man, Kylie stressed (8)
I believe the answer is:
ladylike
'polite' is the definition.
(thesaurus)
'young man kylie stressed' is the wordplay.
I cannot really understand how this works, but
'young' could be 'y' and 'y' is found within the answer.
'man' could be 'lad' (I have seen 'Young man' mean 'lad' so perhaps 'man' could also mean 'lad') and 'lad' is located in the answer.
The remaining letters 'like' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for ladylike that I've seen before include "In manner of genteel or titled woman" , "Graciously feminine" , "Of a woman, refined and genteel" , "Refined and fastidious" , "Typical of a well-mannered woman" .)