ambergris
Ambergris (noun) means a firm, waxy material, greyish to blackish in colour, that can catch fire and is produced inside the gut of sperm whales; it is used in making perfume.
Etymology
From Old French ambre gris (“grey amber”). Though the term was initially spaced as two words, single-word forms predominated by the 19th century. In the 17th century, folk etymologies interpreting the term as amber grease or amber [of] Greece enjoyed some popularity.