the tree Santalum album (=Sirium myrtifolium) of Santalaceae family.

its yellow, fragrant wood.

the tree Aquilaria agallocha of Thymelacaceae family.

its wood.

a balsamic resin obtained from certain tropical Asiatic trees (genus Styrax of the storax family), used in medicine and perfumery and as incense; benzoin.

any of various small plants composed of a particular fungus and a particular alga growing in an intimate symbiotic association and forming a dual plant, commonly adhering in coloured patches or spongelike branches to rock; lichen.