• (n.) A machine generating more than one pressure wave; a multiphaser.
Pol'y·phas`er noun (Electricity) A machine generating more than one pressure wave; a multiphaser. 
polyphaser 1. A machine generating more than one pressure wave; a multiphaser. 2. Consisting of, or occurring, in a number of separate stages. With reference to an electrical device, or circuit, a polyphaser is designed to supply or to use simultaneously several alternating currents of the same voltage and frequency but with different phases.