bone marrow

bone marrow

noun

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

First Known Use of BONE MARROW

1893

Rhymes with BONE MARROW

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

bone marrow

noun    (Medical Dictionary)

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

bone marrow

noun    (Concise Encyclopedia)

Soft, gelatinous tissue that fills bone cavities. Red bone marrow contains stem cells, progenitor cells, percursor cells, and functional blood cells (see reticuloendothelial system). Lymphocytes mature in the lymphoid organs (see lymphoid tissue). All other blood-cell formation occurs in red marrow, which also takes part in destruction of old erythrocytes (red blood cells). Yellow bone marrow mainly stores fats. Because the leukocytes (white blood cells) produced in bone marrow are involved in immune defenses, marrow transplants can treat some types of immunodeficiency. Radiation and some anticancer drugs can damage marrow and impair immunity. Bone-marrow examination helps diagnose diseases related to blood and blood-forming organs.

Variants of BONE MARROW

bone marrow or myeloid tissue