Skip to Content
Medical Term:


Pronunciation: hēm


  1. The porphyrin chelate of iron in which the iron is Fe(II) (or Fe2+); the oxygen-carrying, color-furnishing, prosthetic group of hemoglobin.
  2. Iron complexed with nonporphyrins but related tetrapyrrole structures (biliverdin heme).
  3. Iron chelated with any porphyrin, irrespective of the valence state of the iron atom.

Synonym(s): ferroheme, ferroprotoporphyrin, reduced hematin

[G. haima, blood]