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

That level of hormone then stimulates the bone marrow, which boosts red blood cells, which increases your oxygen-carrying capacity. —Amy Woodyatt, CNN Money, 13 May 2025

On the menu was bone marrow, charred octopus with tentacles sprawling off the serving platter, and a deep-red cherry jubilee with an uncanny resemblance to blood (Isabelle even used a flambé technique at the table to wow her guests). —Ginger Perra, Better Homes & Gardens, 10 May 2025

Early in her treatment, her oncologist urged her to consider bone marrow transplantation, a potential cure. —Faisal Kutty, MSNBC Newsweek, 8 May 2025

Weinstein, who was diagnosed with bone marrow cancer in 2024, had been imprisoned on Rikers Island. —Michaela Zee, Variety, 18 Apr. 2025

Word History

First Known Use

1590, in the meaning defined above

Rhymes for bone marrow

• caballero
• mescalero
• aero
• faro
• garo
• narrow
• pharaoh
• sparrow
• taro
• bolero
• bracero
• estero

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