Real Dictionary

gauge
A gauge is a device that measures the amount or quantity of something and shows the amount measured.
verb: If you gauge the speed or strength of something, or if you gauge an amount, you measure or calculate it, often by using a device of some kind.

gauge in American English
a standard measure or scale of measurement
noun: a standard of measure or measurement
transitive verb: to determine the exact dimensions, capacity, quantity, or force of; measure

gauge in British English
to measure or determine the amount, quantity, size, condition, etc, of
adjective: (of a pressure measurement) measured on a pressure gauge that registers zero at atmospheric pressure; above or below atmospheric pressure
noun: a standard measurement, dimension, capacity, or quantity