A vocabulary of landscape — a landscape of words 1467 entries

water table

WAH-ter TAY-buhl
The upper surface of the zone of saturated ground — the level below which every pore and fracture in the soil and rock is filled with water. Above the water table, the ground is merely damp; below it, the ground is full. The water table rises with rain and falls with drought, and its depth determines what can grow, where wells must reach, and whether basements flood.
Etymology
“Water” from Old English “wæter”; “table” from Old French “table,” from Latin “tabula” (flat board, plank). The geological/hydrological sense — the upper level of groundwater saturation — draws on “table” in its sense of a flat, level surface, first recorded in this usage in the 19th century.