Pumps and pump-heads comprising internal pressure-absorbing member

An exemplary pump includes a pump housing defining a pump cavity, a movable pumping member situated in the pump cavity, and at least one pressure-absorbing member located inside the pump housing. The housing also has an inlet and an outlet, and includes at least one interior non-wearing location that contacts liquid in the pump housing when the pump housing is primed with the liquid. The movable pumping member, when driven to move, urges flow of the liquid from the inlet through the pump cavity to the outlet. The at least one pressure-absorbing member is located inside the pump housing at the non-wearing location and contacts the liquid. The pressure-absorbing member has a compliant property to exhibit a volumetric compression when subjected to a pressure increase in the liquid contacting the pressure-absorbing member, the volumetric compression being sufficient to alleviate at least a portion of the pressure increase.