definition of hemoglobin
Hemoglobin (/ËhiËmÉËÉ¡loÊbáµ»n, ËhÉ-, -moÊ-/); also spelled haemoglobin and abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein in the red blood cells of all vertebrates (with the exception of the fish family Channichthyidae) as well as the tissues of some invertebrates.