Knight interrupting prophet shows disdain (5)
I believe the answer is:
sneer
'disdain' is the definition.
(thesaurus)
'knight interrupting prophet' is the wordplay.
'knight' becomes 'n' (chess abbreviation).
'interrupting' means one lot of letters goes inside another.
'prophet' becomes 'seer' (both can mean someone who tells the future).
'n' inserted into 'seer' is 'SNEER'.
'shows' acts as a link.
(Other definitions for sneer that I've seen before include "Show contempt by contorting the face" , "Dig" , "Show contempt with scornful expression or words" , "Scoff, scorn" , "Curl one's lip" .)