bone marrow


Definition of bone marrow 

: a soft highly vascular modified connective tissue that occupies the cavities of most bones and occurs in two forms:

a : one that is yellowish, consists chiefly of fat cells, and is found especially in the cavities of long bones

b : one that is reddish, is the chief site of blood cell formation, and occurs in the normal adult in cancellous tissue especially of certain flat bones

called also red marrow

Examples of bone marrow in a Sentence

Recent Examples on the Web

Leukemia refers to a group of cancers that affect blood cells, which are normally produced by bone marrow. Sarah Jacoby, SELF, "WWE Star Roman Reigns Reveals Leukemia Diagnosis: 'I Will Beat This and I Will Be Back'," 23 Oct. 2018 John will have to have another bone marrow biopsy this month to see if the cancer is still present or has grown. Terry Tang, The Seattle Times, "Stem cell transplant cements Arizona men’s father-son bond," 10 Sep. 2018 Court documents list the boy’s ultimate cause of death as viral and bacterial bronchopneumonia with bone marrow suppression and anoxic brain injury. Bradford Betz, Fox News, "Man gets 10 years for killing girlfriend's 2-year-old son," 1 Aug. 2018 This final blow may prompt a further genetic mutation, activating the malignant potential of these first two factors and igniting a process in which the bone marrow's production of immature lymphocytes spins out of control. Melissa Healy,, "New 'unified theory' of childhood leukemia raises possibility of preventing the disease," 23 May 2018 The bioreactor would mimic the environment inside bone marrow, the sponge-like tissue that produces platelets. Jonathan Saltzman,, "Department of Defense gives $3.5m to biotech making blood platelets from stem cells," 27 June 2018 The inventive menu, created with beer pairings in mind, includes starters such as escargot, beer cheese, duck confit nachos and roasted bone marrow, as well as pub fare such as poutine and steak and frites. Katherine Rodeghier,, "Midwest eats: Spice up your meal by dining in one of these repurposed restaurants," 26 June 2018 Among other changes, the new version is derived from stem cells harvested more easily from their blood rather than bone marrow, as was the case with the old version. Adam Feuerstein, STAT, "New Bluebird data show promising benefits for gene therapy, if they last," 15 June 2018 Four months later, the cancer returned, this time in his bone marrow. Jacob Carpenter, Houston Chronicle, "‘Honorary Owl,’ who developed special bond with Rice football, dies at 10," 3 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'bone marrow.' 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 bone marrow

1850, in the meaning defined above

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Statistics for bone marrow

Last Updated

8 Dec 2018

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Time Traveler for bone marrow

The first known use of bone marrow was in 1850

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More Definitions for bone marrow

bone marrow


English Language Learners Definition of bone marrow

: a soft substance that fills the bones of people and animals

bone marrow


Kids Definition of bone marrow

: a soft tissue rich in blood vessels that fills the spaces of most bones and includes one type that is red and produces red blood cells and white blood cells and another type that is yellow and contains fat

bone marrow


Medical Definition of bone marrow 

: a soft highly vascular modified connective tissue that occupies the cavities and cancellous part of most bones and occurs in two forms:

a : a whitish or yellowish bone marrow that consists chiefly of fat cells and is found especially in the cavities of the long bones

called also yellow marrow

b : a reddish bone marrow that contains little fat, is the chief site of red blood cell and blood granulocyte formation, and occurs in the normal adult in cancellous tissue especially of certain flat bones

called also red marrow

More from Merriam-Webster on bone marrow

Rhyming Dictionary: Words that rhyme with bone marrow Encyclopedia article about bone marrow

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the figure or shape of a crescent moon

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