A pump for pumping fluid, wherein the pump includes a working chamber, a piston assembly configured for reciprocating within the working chamber to thereby displace fluid, a piston actuator being rigidly assembled with the piston assembly at least in a working mode of the pump to thereby transmit drive energy to the piston assembly to reciprocate along a common rigid axis of the piston-actuator-assembly, and a bearing arrangement bearing the piston assembly and the piston actuator in the pump so that the piston-actuator-assembly provided by the piston assembly and the piston actuator is capable of performing a pendulum-type compensation motion around a pendulum point at the piston actuator on the common rigid axis.