ETYM Old Eng. marou, mary, maruh, AS. mearg, mearh; akin to OS. marg, Dutch merg, German Mark, Old High Germ. marg, marag, Icel. mergr, Swed. merg, Dan. marv, Skr. majjan; cf. Skr. majj to sink, Latin mergere. Related to Merge.
1. The fatty network of connective tissue that fills the cavities of bones; SYN. bone marrow.
2. Very tender and very nutritious tissue from marrowbones; SYN. bone marrow.