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)

Keep scrolling for more

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 People with sickle-cell disease, a congenital illness, lack an enzyme that helps the hemoglobin molecules in their blood maintain shape. Ricardo Nuila, The New Yorker, "The Coronavirus Surge That Texas Could Have Seen Coming," 26 June 2020 As a result, the red blood cell hemoglobin can extract more lifesaving oxygen and move it into the general circulation. The Conversation, oregonlive, "The science behind why this is the safest way to breathe to avoid coronavirus," 19 June 2020 As a result, the red blood cell hemoglobin can extract more lifesaving oxygen and move it into the general circulation. The Conversation, "The right way to breathe during the coronavirus pandemic," 19 June 2020 Overall, 12 of the 13 patients treated with the Agios drug called mitapivat achieved meaningful hemoglobin responses in the Phase 2 study. Adam Feuerstein, STAT, "Agios drug demonstrates strong response in patients with inherited blood disorder," 12 June 2020 In such cases, Berra said, the dose can be lowered and hemoglobin will quickly revert to normal. Los Angeles Times, "How a discovery that brought us Viagra could help those battling the coronavirus," 5 Apr. 2020 Oxbryta works by making oxygen attach more tightly to hemoglobin. Adam Feuerstein, STAT, "Global Blood secures FDA approval for new pill to treat sickle cell disease," 25 Nov. 2019 On Wednesday, the results indicated severe dehydration with a low hemoglobin count and she was directed to the ER. oregonlive, "Portland Pilots guard Chase Adams under self-quarantine after grandmother diagnosed with coronavirus," 27 Mar. 2020 With methemoglobinemia, the body's hemoglobin is able to carry oxygen, but cannot deliver it to the body's tissues, per the U.S. National Library of Medicine (NLM). Maggie O'neill, Health.com, "What is Methemoglobinemia? What to Know About the Rare Disorder That Turned One Woman’s Blood Blue," 19 Sep. 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.

See More

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

Keep scrolling for more

Learn More about hemoglobin

Time Traveler for hemoglobin

Time Traveler

The first known use of hemoglobin was in 1869

See more words from the same year

Statistics for hemoglobin

Last Updated

5 Jul 2020

Cite this Entry

“Hemoglobin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hemoglobin. Accessed 8 Aug. 2020.

Keep scrolling for more

More Definitions for hemoglobin

hemoglobin

noun
How to pronounce hemoglobin (audio)

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

Keep scrolling for more

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

Comments on hemoglobin

What made you want to look up hemoglobin? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

Test Your Vocabulary

Original Meanings Quiz

  • rembrandt painting a young scholar and his tutor
  • Which of the following is the earliest known sense of the word awe?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!