One of these is water table, which, if you recall, can have two completely different meanings.
If you’re talking about a water table in the sense of ground water, Wikipedia says:
The water table is the surface where the water pressure head is equal to the atmospheric pressure (where gauge pressure = 0). It may be conveniently visualized as the 'surface' of the subsurface materials that are saturated with groundwater in a given vicinity. However, saturated conditions may extend above the water table as surface tension holds water in some pores below atmospheric pressure. Individual points on the water table are typically measured as the elevation that the water rises to in a well screened in the shallow groundwater.
If you’re talking about a water table as an architectural element, Wikipedia says:
A water table is a masonry architectural feature that consists of a projecting course that deflects water running down the face of a building away from lower courses or the foundation. A water table may be found near the base of a wall or at a transition between materials, such as from stone to brick.
I love the english language. And architecture. And specification writing. No other profession offers entertainment like this without having to pay for it.