bone marrow

noun

: a soft substance that fills the bones of people and animals

Full Definition of BONE MARROW

: 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

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First Known Use of BONE MARROW

1893

Rhymes with BONE MARROW

broad arrow, house sparrow, song sparrow, straight-arrow, tree sparrow, wheelbarrow

BONE MARROW Defined for Kids

bone marrow

noun

Definition of BONE MARROW for Kids

: a soft tissue rich in blood vessels that fills the spaces of most bones and includes one type that is red and produces red blood cells and white blood cells and another type that is yellow and contains fat

Medical Dictionary

bone marrow

noun

Medical Definition of BONE MARROW

: 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 consisting chiefly of fat cells and predominating in the cavities of the long bones—called also yellow marrow b : a reddish bone marrow containing little fat, being the chief seat of red blood cell and blood granulocyte formation, and occurring in the normal adult only in cancellous tissue especially in certain flat bones—called also red marrow