Definition of "hemoglobin" []

• The iron-containing respiratory pigment in red blood cells of vertebrates, consisting of about 6 percent heme and 94 percent globin. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The extent to which the hemoglobin is saturated with oxygen."
• "Munich had already done significant work on the structure of hemin, the organic pigment in hemoglobin, when he synthesized it from simpler organic molecules in 1928."
• "Guidelines published in 2007 by the Society of Thoracic Surgeons say that when hemoglobin is six or under, equivalent to a red-blood-cell level below 18%, transfusions can be life-saving."