Key Points. 1  Megaloblasts are large nucleated RBC precursors with noncondensed chromatin. 2  The most common causes of megaloblastic, macrocytic anemia are deficiency or defective utilization of vitamin B12 or folate. 3  Do CBC, RBC indices, reticulocyte count, and peripheral smear.
Wiktionary (0.00 / 0 votes) Rate this definition: vein (Noun). A blood vessel that transports blood from the capillaries back to the heart. vein (Noun). (used in plural veins) The entrails of a shrimp. vein (Noun). In leaves, a thickened portion of the leaf containing the vascular bundle. vein (Noun).
The noun VENA CAVA has 1 sense: 1  1. either of two large veins that return oxygen-depleted blood to the right atrium of the heart. 2  Meaning: 3  Either of two large veins that return oxygen-depleted blood to the right atrium of the heart. 4  Classified under: 5  Nouns denoting body parts. 6  Hypernyms (vena cava is a kind of...): vein; vena; venous blood vessel (a blood vessel that carries blood from the capillaries toward the heart) Hyponyms (each of the following is a kind of vena cava): inferior vena cava; postcava (receives blood from lower limbs and abdominal organs and empties into the posterior part of the right atrium of the heart; formed from the union of the two iliac veins)