bone marrow

noun

: 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 The work highlights the spectrum of risk for Covid becoming chronic — from high levels for people with blood cancers requiring bone marrow transplants, lower risk for people taking immune-suppressing drugs for autoimmune illness, and little risk for those with intact immunity. Elizabeth Cooney, STAT, 24 Jan. 2024 Snyder, who was diagnosed with acute myeloid leukemia in 2015, teamed up with actor Jason Momoa to encourage people to join the Be the Match bone marrow donor registry Travis Snyder, founder of The Color Run, has died. Ingrid Vasquez, Peoplemag, 3 Dec. 2023 Because of problems with bone marrow and surrounding organs that occur with brain and spine radiation, proton beam radiation therapy is often recommended. Dominique Fluker, Essence, 12 Jan. 2024 Our body's nervous system is controlled solely by the brain; the immune system involves the bone marrow, spleen, thymus, tonsils, mucous membranes and skin. Karen Weintraub, USA TODAY, 1 Jan. 2024 For patients being treated, this process involves first harvesting their bone marrow stem cells, which then get CRISPR-ed in a specialized lab. Beth Mole, Ars Technica, 8 Dec. 2023 Lymphocytes are a type of white blood cell that are developed in bone marrow but triggered by lymph nodes, which are sacks of tissue that filter fluid in your body for outside invaders, according to the Cleveland Clinic. Irene Wright, Miami Herald, 7 Feb. 2024 The heroic task of constantly replenishing these ranks, and making sure the balance of different types of blood cells is right, falls to a primitive reserve of stem cells that reside deep in the bone marrow. Megan Molteni, STAT, 22 Jan. 2024 In the new therapy, physicians remove a person’s own bone marrow stem cells, edit them with exa-cel, destroy the rest of the person’s untreated bone marrow and then reinfuse the edited cells. Sara Reardon, Scientific American, 8 Dec. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'bone marrow.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1590, in the meaning defined above

Time Traveler
The first known use of bone marrow was in 1590

Dictionary Entries Near bone marrow

Cite this Entry

“Bone marrow.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bone%20marrow. Accessed 19 Mar. 2024.

Kids Definition

bone marrow

noun
: a soft tissue rich in blood vessels that fills the cavities of most bones and occurs in two forms:
a
: one that is yellowish and fatty and is found especially in long bones (as the femur)
b
: one that is reddish, is the main place where blood cells are formed, and in adults is limited especially to certain flat or short bones (as the ribs)

Medical Definition

bone marrow

noun
: 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

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