Meaning of pernicious anemia

perni'cious ane'mia

Pronunciation: [key]
— Pathol. Pathol.
  1. a severe anemia caused by the diminution or absence of stomach acid secretion, with consequent failure of the gastric mucosa to secrete the intrinsic factor necessary for the absorption of vitamin B, characterized by a great reduction in the number of red blood cells and an increase in their size.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.