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 October, Weinstein was diagnosed with bone marrow cancer and has been imprisoned on Rikers Island while awaiting the retrial. —Jordan Moreau, Variety, 29 Jan. 2025

The 83-year-old was diagnosed with chronic lymphocytic leukemia, a type of blood cancer that begins in the bone marrow, in 2005. —Berkeley Lovelace Jr., NBC News, 25 Dec. 2024

In an exclusive interview with PEOPLE, Turner opens up about how receiving a bone marrow cancer diagnosis in March affected his priorities as a newlywed Comments Gerry Turner is opening up about his divorce from Theresa Nist — and a life-changing diagnosis. —Esther Kang, People.com, 11 Dec. 2024

The 72-year-old former reality television star revealed thathe is currently battling an incurable and slow form of bone marrow cancer known as Waldenström’s macroglobulinemia in a new interview with People Magazine on Wednesday, December 11. —Lexi Lane, SPIN, 11 Dec. 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