Like white peacocks (4)
I believe the answer is:
rare
'like white peacocks' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rare that I've seen before include "Not easily come by like undercooked meat" , "may be bloody" , "Might a four-leaf clover be so" , "Excellent; uncommon" , "Especially good" .)