Answer:

marrow

Answer	Crossword Clue
MARROW	Bone tissue
MARROW	Source of red blood cells
MARROW	Bone substance

MARROW	Bone material properly eaten with a scoop
MARROW	Bone filler
MARROW	Blood-cell source
MARROW	Kind of bone.
MARROW	Squash variety
MARROW	Pith
MARROW	Blood cells' birthplace