[L. lignum, wood; and vitae, of life.] The name of the wood of the guaiacum tree, which grows in the West Indies and South America. The wood is very heavy, hard, close-grained, and tough, and is used for making pulleys, wheels in ships' blocks, pestles, rulers, and other articles which require to be of a tough material. The resinous juice of the tree is used in medicine in cases of rheumatism and skin diseases.