A combination mixing pitcher having a mixer subassembly that incorporates an impeller which is reciprocally longitudinally slidably movable but not rotatable within the pitcher. The impeller is fixed to one end of a plunger rod that reciprocates slidably through a matingly engagable axial channel in a lid that peripherally closes the pitcher mouth. The impeller employs a plurality of flat, radially pitched, fan shaped blades that are in radially equally spaced relationship to each other and that extend between a central hub and a peripheral polygonally configured rim. The mixer subassembly maximizes mixing of a liquid in the pitcher with a minimum of time and energy and with no spillage.