Diploe

noun

1. The spongy, porous, bony tissue between the hard outer and inner bone layers of the cranium.
2. In anatomy, the light spongy substance or open cancellated or reticulated structure of bone between the hard dense inner and outer tables of the cranial bones.
3. In botany, the parenchyma of a leaf, lying between the two epidermal surfaces. Also called meditullium.
4. The soft, spongy, or cancellated substance between the plates of the skull.
5. The thin layer of soft, spongy or cancellate tissue between the bone plates which constitute the skull.