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

In the months that followed the diagnosis, Thomas underwent several medical procedures, including chemotherapy, neck surgery and a bone marrow transplant, the hospital said. —Maria Sole Campinoti, CNN, 2 Dec. 2024

Harvey Weinstein diagnosed with cancer Andrew Kelly / Pool via AFP - Getty Images file Disgraced Hollywood mogul Harvey Weinstein is undergoing treatment at a New York prison for chronic myeloid leukemia, an uncommon form of cancer of the bone marrow, two sources said. —Elizabeth Robinson, NBC News, 22 Oct. 2024

The American Cancer Society states that chronic myeloid leukemia (CML) is a type of cancer that develops in the blood-forming cells of the bone marrow and invades the blood, and that 15 percent of leukemias in adults are CML. —Charisma Madarang, Rolling Stone, 22 Oct. 2024

Harvey Weinstein rushed to hospital for emergency heart surgery According to the American Cancer Society, chronic myeloid leukemia is a type of cancer that starts in the blood-forming cells of the bone marrow and invades the blood. —Aaron Katersky, ABC News, 21 Oct. 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