The most common and most likely answer to this crossword clue is the 12 letter word FRANKINCENSE
I've seen this crossword clue in The Guardian
F
R
A
N
K
I
N
C
E
N
S
E
More clues leading to the result FRANKINCENSE
- Old German in moving scene offers Christmas gift
- King’s present unfeigned anger
- Anger follows sincere Christmas gift
- Open with anger first Christmas present
- Birthday gift given with loud and offensive anger?
- Burnt offering, plain outrage
- Smelly stuff gives fellow utter outrage
- Feminine anger about foul-smelling resin
- Source of pleasant scent making fellow get angry after row
- Unconcealed urge to get an original Christmas gift
Buddy explains!

The straight part
We know that "King’s present" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case king’s present = frankincense.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does FRANKINCENSE mean?
FRANKINCENSE noun- A type of incense obtained from the Boswellia thurifera tree.