King hates fancy red suit (6)
I believe the answer is:
Here is my best explanation:
'red suit' is the definition.
(I've seen this before)
'king hates fancy' is the subsidiary indication.
'king' becomes 'r' (r is abbreviation for rex).
'fancy' indicates anagramming the letters.
'rhates' is an anagram of 'hearts'.
(Other definitions for hearts that I've seen before include "Scots club nickname; suit", "Major suit at cards", "Central parts", "Centres", "Suit for vital organs", "See 23", "Vital suit", "Vital organs in the pack", "Suit of cards" and "Playing-card suit".)