in botany, a genus of the monoecia polyandria clas. The calyx has four leaves; it has no corolla, but numerous filaments; the calyx of the male consists of four leaves in the form of a globe; it has no corolla, but a couple of styli; and the capsules, which are numerous, are round, with a double valve, and contains many seeds. There are two species, both natives of America. This tree yields a fragrant resin, called liquidamber, which resolves and opens obstructions.