Ladanum

Lad″a‐num (?), n. [L. ladanum, ledanum, Gr. λάδανον, λήδανον, fr. λη̑δον name of a shrub, mastic; cf. Per. lādan, lāden. Cf. Laudanum.] A gum resin gathered from certain Oriental species of Cistus. It has a pungent odor and is chiefly used in making plasters, and for fumigation. [Written also labdanum.]