hemoglobin

noun
he·​mo·​glo·​bin | \ ˈhē-mə-ˌglō-bən How to pronounce hemoglobin (audio) \

Definition of hemoglobin

1 : an iron-containing respiratory pigment of vertebrate red blood cells that consists of a globin composed of four subunits each of which is linked to a heme molecule, that functions in oxygen transport to the tissues after conversion to oxygenated form in the gills or lungs, and that assists in carbon dioxide transport back to the gills or lungs after surrender of its oxygen
2 : any of numerous iron-containing respiratory pigments of various organisms (such as invertebrates and yeasts)

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Did You Know?

When filled with oxygen, the hemoglobin in your blood is bright red; returning to the lungs without its oxygen, it loses its brightness and becomes somewhat bluish. Hemoglobin levels can change from day to day, and may be affected by such factors as a lack of iron in the diet, a recent loss of blood, and being pregnant. When you give blood, a nurse first pricks your finger to test your hemoglobin level; a low hemoglobin count indicates anemia and may mean that you shouldn't give blood that day. Mild anemia is generally of little importance, but some types can be very serious.

Examples of hemoglobin in a Sentence

Recent Examples on the Web

High bone density, a hemoglobin that boosts malaria resistance, and a third retinal cone that improves color vision are some human examples. Jill Kiedaisch, Popular Mechanics, "Could Shark DNA Help Fight Cancer in Humans?," 22 Feb. 2019 This inherited condition damages the hemoglobin in your red blood cells, which is responsible for transporting oxygen in your blood. Korin Miller, SELF, "10 Things That Can Cause Blood in Your Urine," 19 Sep. 2018 Hand ID takes advantage of the camera’s infrared sensor to read the absorption characterization of hemoglobin in the veins of your hand. Michael Simon, PCWorld, "LG G8 hands-on: Could the future of smartphones be in the palm of my hand?," 24 Feb. 2019 The therapy aims to treat beta thalassemia, a disease caused by a defective gene that hinders production of hemoglobin, which carries oxygen through the blood, and can cause severe anemia, fatigue and organ damage. Joseph Walker, WSJ, "Biotech Proposes Paying for Pricey Drugs by Installment," 8 Jan. 2019 Landsteiner's Discoveries Studying earlier experiments with animals, scientists had noticed that these foreign bodies were broken up in the human bloodstream by hemoglobin, which resides on red blood cells and carries oxygen through the body. David Grossman, Popular Mechanics, "What Different Blood Types Mean (And How To Find Out Yours)," 28 Dec. 2018 Leghemoglobin is an iron-containing protein pulled from soybean roots that’s similar to hemoglobin, an oxygen-carrying protein in red blood cells. Beth Mole, Ars Technica, "PETA roasts Impossible Burger for rat tests, suggests patties cause cancer," 11 Aug. 2018 Methemoglobinemia is a rare blood disorder that reduces the amount of hemoglobin, the protein that carries oxygen, in the blood. Korin Miller, SELF, "The FDA Wants Benzocaine Teething Products Taken Off the Market," 24 May 2018 The most recent success has been hemoglobin (by [Max Ferdinand] Perutz); the model of this protein contains 10,000 atoms. Daniel C. Schlenoff, Scientific American, "“Foul Treachery” of Trotsky and Lenin in 1918; Phineas Gage’s Brain in 1868," 13 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hemoglobin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of hemoglobin

1869, in the meaning defined at sense 1

History and Etymology for hemoglobin

International Scientific Vocabulary, short for earlier hematoglobulin

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Last Updated

20 Mar 2019

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Time Traveler for hemoglobin

The first known use of hemoglobin was in 1869

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More Definitions for hemoglobin

hemoglobin

noun

English Language Learners Definition of hemoglobin

technical : the part of blood that contains iron, carries oxygen through the body, and gives blood its red color

hemoglobin

noun
he·​mo·​glo·​bin | \ ˈhē-mə-ˌglō-bən How to pronounce hemoglobin (audio) \

Kids Definition of hemoglobin

: a protein of red blood cells that contains iron and carries oxygen from the lungs to the tissues and carbon dioxide from the tissues to the lungs

hemoglobin

noun
he·​mo·​glo·​bin
variants: or chiefly British haemoglobin \ ˈhē-​mə-​ˌglō-​bən How to pronounce haemoglobin (audio) \

Medical Definition of hemoglobin

1 : an iron-containing respiratory pigment of vertebrate red blood cells that functions primarily in the transport of oxygen from the lungs to the tissues of the body, that consists of four polypeptide chains of which two are of the type designated alpha and two are of one of the types designated beta, gamma, or delta and each of which is linked to a heme molecule, that combines loosely and reversibly with oxygen in the lungs or gills to form oxyhemoglobin and with carbon dioxide in the tissues to form carbaminohemoglobin, that in humans is present normally in blood to the extent of 14 to 16 grams in 100 milliliters expressed sometimes on a scale of 0 to 100 with an average normal value (as 15 grams) taken as 100, and that is determined in blood either colorimetrically or by quantitative estimation of the iron present — see fetal hemoglobin, hemoglobin a — compare carboxyhemoglobin, methemoglobin
2 : any of numerous iron-containing respiratory pigments of various organisms (as invertebrates and yeasts)

Other Words from hemoglobin

hemoglobinic or chiefly British haemoglobinic \ ˌhē-​mə-​glō-​ˈbin-​ik How to pronounce haemoglobinic (audio) \ adjective
hemoglobinous or chiefly British haemoglobinous \ -​ˈglō-​bə-​nəs How to pronounce haemoglobinous (audio) \ adjective

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More from Merriam-Webster on hemoglobin

Spanish Central: Translation of hemoglobin

Nglish: Translation of hemoglobin for Spanish Speakers

Britannica English: Translation of hemoglobin for Arabic Speakers

Britannica.com: Encyclopedia article about hemoglobin

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