Nativity wise men (4)
I believe the answer is:
magi
'nativity wise men' 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 Bethlehem" , "Eastern men of lore; Epiphany figures" , "Persian wise men" , "Wise men, visitors to Bethlehem" , "Star witnesses" .)