An original Christmas gift (12)
I believe the answer is:
frankincense
'christmas gift' is the definition.
(gift given to Jesus)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for frankincense that I've seen before include "Nativity gift; aromatic tree resin" , "Gift of one of the Magi" , "One of the gifts of the Magi" , "Aromatic gum resin - an original Christmas present!" , "Gum resin used as incense" .)