A standard or scale of measurement. A standard dimension, quantity, or capacity. An instrument for measuring or testing. A means of estimating or evaluating; a test: a gauge of character. See Synonyms at standard. Nautical The position of a vessel in relation to another vessel and the wind. The distance between the two rails of a railroad. The distance between two wheels on an axle. The interior diameter of a shotgun barrel as determined by the number of lead balls of a size exactly fitting the barrel that are required to make one pound. Often used in combination: a 12-gauge shotgun. The amount of plaster of Paris combined with common plaster to speed setting of the mixture. Thickness or diameter, as of sheet metal or wire. The fineness of knitted cloth as determined by the number of loops per 1 1/2 inches. To measure precisely. To determine the capacity, volume, or contents of. To evaluate or judge: gauge a person's ability. To adapt to a specified measurement. To mix (plaster) in specific proportions. To chip or rub (bricks or stones) to size.