1.
the ratio of the volume occupied by packed red blood cells to the volume of the whole blood as measured by a hematocrit
2.
a measuring instrument to determine (usually by centrifugation) the relative amounts of corpuscles and plasma in the blood
The first recipe for a lasagna type dish was found to be from a British cookbook in the 14th century. Therefore, Italians were not the first ones to come up with the popular dish as believed.