New Testament trio (4)
I believe the answer is:
magi
'new testament trio' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for magi that I've seen before include "Nativity story wise men" , "members of priestly caste" , "Priests" , "Wise men, visitors to Bethlehem" , "The three Wise Men of Bethlehem" .)