The downstream flow of water through the permeable deposits that underlie a stream and that are more or less limited by rocks of low permeability.

The underground flow or movement of water in an aquifer.

the discharge from the bottom of a thickener, which should have a high concentration of settled waste solids from the solid-liquid suspension added to a thickener.

Condition caused when a floating-point value is too small to be represented.

An exception condition that occurs when the result of a floating-point operation is smaller than the smallest normalized number. On systems that support it, fast underflow is an efficient method of handling this exception.

A condition that occurs when the result of an operation is less than the smallest possible nonzero number. IBM.

(ISO) The state in which a calculator shows a zero indicator for the most significant part of a number while the least significant part of the number is dropped. For example, if the calculator output capacity is four digits, the number .0000432 will be shown as .0000. See: arithmetic underflow.

An error condition that occurs when a calculation produces a result too small for the computer to represent.