chyme
So that white and red blood cells can pass through the capillaries
Because if blood pressure in lung capillaries was as high as it is in body capillaries, the hydrostatic pressure caused by this blood pressure would force blood plasma out of the capillaries into intracellular spaces (as is done in body capillaries) or into the alveoli. This would reduce the efficiency of gas exchange.
Interstitial fluid (or tissue fluid) is a solution that surrounds the cells of animals. It is the main component of the extracellular fluid, it includes plasma and transcellular fluid. The interstitial fluid is found in the interstitial spaces, also known as the tissue spaces.
Found in spaces between cells and becomes lymph when it enters lymph capillaries.
Intercostal spaces
The spaces between leaf veins are called areoles or areolae.
pore spaces
blood-brain barrier (!)
the spaces between the teeth of a comb are called umpernaters :) that's their scientific name.
Rhythm
cementation
Chorionic Villi with Fetal capillaries Intervillous Spaces Decidua basalis with maternal capillaries