ball valve a. The periodic or intermittent blockage of a tubular structure by a foreign body.
cumulative a. See cumulative effect, under effect.
sparing a. The lowering of the requirement for an essential food factor in the diet
caused by the presence of another food factor which, by itself, is not essential.
specific dynamic a. The increase in heat production during digestion; it is greater for protein than for fat or carbohydrate.
synergistic a. The coordinated activity of two or more structures or drugs whereby the
combined effect is greater than the sum of the effects produced by their actions alone.