Ethical road evenly worn by a princess (5)
I believe the answer is:
tiara
'worn by a princess' is the definition.
I can't tell whether this definition defines the answer.
'ethical road evenly' is the wordplay.
'evenly' means one should take alternating letters (the letters in even-numbered positions).
'ethical'+'road'='ethicalroad'
The alternating letters of 'ethicalroad' are 'TIARA'.
Can you help me to learn more?
(Other definitions for tiara that I've seen before include "It might go to one's head" , "It bejewels" , "Decorative headband" , "Jewelled head wear" , "Small crown" .)