- Zone melting
a process of purifying any of various metals and other materials, as germanium or silicon, by passing it in bar form through an induction coil.
- Zone of illuviation
. zone of illuviation See B horizon. zone of accumulation See B horizon.
- Zone of saturation
noun the ground below the water table
- Zone plate
a plate or screen with alternating opaque and transparent concentric rings that focus light by diffraction.