Yuletide wise trio (4)
I believe the answer is:
magi
'yuletide wise trio' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for magi that I've seen before include "The three Wise Men of the gospels" , "Star witnesses" , "The Three Kings" , "Sorcerers in ancient times" , "Travellers in NT" .)