Source : Webster's Revised Unabridged Dictionary (1913)

Guaiacol \Guai"a*col\, n. [Guaiacum + -ol.] (Chem.)
   A colorless liquid, {C7H8O2}, with a peculiar odor. It is the
   methyl ether of pyrocatechin, and is obtained by distilling
   guaiacum from wood-tar creosote, and in other ways. It has
   been used in treating pulmonary tuberculosis.