Source : Webster's Revised Unabridged Dictionary (1913)

Phthisis \Phthi"sis\, n. [L., fr. Gr. ?, fr. ? to pass or waste
   away: cf. F. phthisie.] (Med.)
   A wasting or consumption of the tissues. The term was
   formerly applied to many wasting diseases, but is now usually
   restricted to pulmonary phthisis, or consumption. See
   {Consumption}.

   {Fibroid phthisis}. See under {Fibroid}.

Source : WordNet®

phthisis
     n : involving the lungs with progressive wasting of the body
         [syn: {pulmonary tuberculosis}, {consumption}, {wasting
         disease}, {white plague}]