By showing a degree of superiority (3)
I believe the answer is:
per
'by' is the definition.
(I've seen this in another clue)
'a degree of superiority' is the wordplay.
'PER' is hidden within the letters.
However, I'm unsure how the hidden word is indicated.
'showing' acts as a link.
Can you help me to learn more?
(Other definitions for per that I've seen before include "According to" , "Preposition indicating by means of" , "For each or every" , "Preposition meaning for each" .)