Synonyms for Labdanum (same or very similar meaning)
WordNet sense 1 (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):
gum labdanumWordNet sense 2 (a soft blackish-brown resinous exudate from various rockroses used in perfumes especially as a fixative):
ladanumFrom the ODE community, based on WordNetadd/edit