What is "agalwood"

Agalloch \Ag"al*loch\ ([a^]g"[a^]l*l[o^]k), ||Agallochum \A*gal"lo*chum\ ([.a]*g[a^]l"l[-o]*k[u^]m), n. [Gr. a`ga`llochon, of Eastern origin: cf. Skr. aguru, Heb. pl. ah[=a]l[=i]m.] A soft, resinous wood ( Aquilaria Agallocha) of highly aromatic smell, burnt by the orientals as a perfume. It is called also agalwood and aloes wood. The name is also given to some other species.