The total mass of circulating red blood cells, and that part of the haematopoietic tissue from which they are derived. ... (05 Mar 2000) ... 
(er´ә-thron) the circulating erythrocytes in the blood, their precursors, and all the body elements concerned in their production.
Type: Term Pronunciation: er′i-thron Definitions: 1. The total mass of circulating red blood cells, and that part of the hematopoietic tissue from which they are derived.