labdanum vs ladanum

labdanum and ladanum both are nouns.

Word	Noun	Adjective	Verb	Adverb
labdanum	Yes	No	No	No
ladanum	Yes	No	No	No

As nouns, labdanum and ladanum are synonyms defined as:

labdanum and ladanum: a soft blackish-brown resinous exudate from various rockroses used in perfumes especially as a fixative

labdanum (noun)	ladanum (noun)
a soft blackish-brown resinous exudate from various rockroses used in perfumes especially as a fixative	a soft blackish-brown resinous exudate from various rockroses used in perfumes especially as a fixative
a dark brown to greenish oleoresin that has a fragrant odor and is used as a fixative in perfumes; obtained as a juice from certain rockroses