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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The popular radio co-host is undergoing treatment for multiple myeloma, a cancer that affects the plasma cells in bone marrow. Sean Krofssik, Hartford Courant, 12 Jan. 2025 Additional tests include bone marrow aspiration and biopsy, imaging studies, and cytochemistry. Doru Paul, Health, 10 Jan. 2025 There's little holes on top that all those healing cells that are in your bone marrow can trickle up into that CartiHeal implant and then come up and then turn into a more cartilage type tissue. Dana Taylor, USA TODAY, 6 Jan. 2025 Also had some bone marrow taken from my hip and put into my foot. Brian Mazique, Forbes, 6 Jan. 2025 See all Example Sentences for bone marrow 

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 24 Jan. 2025.

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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