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

This form of hemoglobin is normally turned off after birth. San Diego Union-Tribune, "Biotech notebook: Public service on stem cell science," 6 July 2019 Juan Caballero, a 69-year old Hallandale Beach resident with sickle cell, participated in a clinical trial for Voxelotor for two years and saw a positive result; his hemoglobin levels rose from dangerously low levels. Cindy Krischer Goodman, sun-sentinel.com, "South Floridians urged to take part in research leading to breakthroughs in fight against sickle cell disease," 8 June 2019 Even lowlanders can acclimate, eventually producing extra red blood cells, which contain hemoglobin, the protein responsible for transporting oxygen throughout the body. Bridget Alex, Discover Magazine, "The World Is Our Niche," 3 June 2019 The proprietary solution is based on hemoglobin, the oxygen-ferrying protein in red blood cells, and is made to show up in ultrasound scans, so researchers can track its flow through the brain. Michael Greshko, National Geographic, "Pig brains partially revived hours after death—what it means for people," 17 Apr. 2019 Pregnant people are more at risk of iron deficiency because their blood volume increases by 20 to 30 percent, calling for more iron to create hemoglobin that can send oxygenated red blood cells all over the body. Kristin Auble, SELF, "9 Facts to Know About Restless Legs Syndrome," 16 Mar. 2019 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

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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Statistics for hemoglobin

Last Updated

10 Jul 2019

Look-up Popularity

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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