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

Sauces range from the traditional (béarnaise, potato butter) to the playful (pineapple hot sauce, bone marrow vinaigrette). —Tori Latham, Robb Report, 4 Oct. 2024

Leukemia is a type of blood cancer that begins in the bone marrow, where the blood cells are produced. —Carrie Madormo, Rn, Health, 26 Sep. 2024

The film also marks the first time Springsteen's wife and E Street Band member Patti Scialfa has publicly spoken about her diagnosis of multiple myeloma, a cancer of plasma cells, which are found in the bone marrow and are an important part of the immune system, per the American Cancer Society. —Ilana Kaplan, Peoplemag, 24 Sep. 2024

In a study published last year in researchers described the development of nanoparticles that carry messenger RNA (mRNA) into stem cells in the bone marrow. —Sara Reardon, Scientific American, 17 Sep. 2024

Word History

First Known Use

1590, in the meaning defined above

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