Where does “ambra” come from?

ambra (Medieval Latin) comes from Arabic عَنْبَر, from Middle Persian ʾmbl — ambergris.

Ancestry of “ambra”, step by step

Step	Language	Word	Meaning
1	Arabic	عَنْبَر	amber; ambergris
2	Middle Persian	ʾmbl	ambergris

ambra — Etymology, Origin & Word History | Etymology Explorer