the fatty network of connective tissue that fills the cavities of bones | a system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response |
the choicest or most essential or most vital part of some idea or experience | |
large elongated squash with creamy to deep green skins | |
very tender and very nutritious tissue from marrowbones | |
any of various squash plants grown for their elongated fruit with smooth dark green skin and whitish flesh | |