|Noah Webster's Dictionary|
1. (n.) The tissue which fills the cavities of most bones; the medulla. In the larger cavities it is commonly very fatty, but in the smaller cavities it is much less fatty, and red or reddish in color.
2. (n.) The essence; the best part.
3. (n.) One of a pair; a match; a companion; an intimate associate.
4. (v. t.) To fill with, or as with, marrow of fat; to glut.
Int. Standard Bible Encyclopedia
mar'-o (moach, chelebh, shiqquy, machah, "to make fat," "to grease"; muelos): Marrow is the nourisher and strengthener of the bones; it is said to moisten the bones: "The marrow (moach) of his bones is moistened" (Job 21:24). The fear of Yahweh "will be health to thy navel, and marrow (shiqquy, margin "refreshing, Hebrew moistening") to thy bones" (Proverbs 3:8). Thus, the expression is used figuratively of the things which alone can satisfy the soul: "My soul shall be satisfied as with marrow (chelebh, "fat") and fatness" (Psalm 63:5); "In this mountain will Yahweh of hosts make unto all peoples a feast of fat things, a feast of wines on the lees, of fat things full of marrow (memuchayim, particle, plural, Pual of machah), of wines on the lees well refined" (Isaiah 25:6). In the Epistle to the Hebrews the writer speaks of the word of God, which is "living, and active, and sharper than any two-edged sword, and piercing even to the dividing of soul and spirit, of both joints and marrow" (Hebrews 4:12).
H. L. E. Luering
Marrow (5 Occurrences)
Hebrews 4:12 For the word of God is living, and active, and sharper than any two-edged sword, and piercing even to the dividing of soul and spirit, of both joints and marrow, and is able to discern the thoughts and intentions of the heart. (WEB KJV WEY ASV DBY WBS YLT NAS RSV NIV)
Job 21:24 His pails are full of milk. The marrow of his bones is moistened. (WEB KJV JPS ASV DBY WBS YLT NAS RSV NIV)
Psalms 63:5 My soul shall be satisfied as with marrow and fatness; and my mouth shall praise thee with joyful lips: (KJV JPS ASV DBY WBS NAS RSV)
Proverbs 3:8 It shall be health to thy navel, and marrow to thy bones. (KJV JPS ASV WBS)
Isaiah 25:6 In this mountain, Yahweh of Armies will make all peoples a feast of fat things, a feast of choice wines, of fat things full of marrow, of well refined choice wines. (WEB KJV JPS ASV DBY WBS YLT NAS RSV)