“starling's”

: a hypothesis in physiology: the flow of fluids across capillary walls depends on the balance between the force of blood pressure on the walls which tends to force fluids out and the osmotic pressure across the walls which tends to force them in due to the greater concentration of dissolved substances in the blood so that the declining gradient in blood pressure from the arterial to the venous end of the capillary results in an outflow of fluids at its arterial end with an increasing inflow toward its venous end

: a statement in physiology: the strength of the heart's systolic contraction is directly proportional to its diastolic expansion with the result that under normal physiological conditions the heart pumps out of the right atrium all the blood returned to it without letting any back up in the veins