Source : Webster's Revised Unabridged Dictionary (1913)

Hematosis \Hem`a*to"sis\, n. [NL., fr. Gr. a"ima`twsis.]
   (Physiol.)
   (a) Sanguification; the conversion of chyle into blood.
   (b) The arterialization of the blood in the lungs; the
       formation of blood in general; h[ae]matogenesis.