Gage

[1] A standard SAE designation of wire sizes, expressed in AWG (American Wire Gage). The larger the gage number, the smaller the wire. Metric wire sizes are expressed in cross-sectional area, which is expressed in square millimeters. Sometimes the spelling "gauge" is also used to designate wire size. However, it is becoming standard to use "gage" for wire size and "gauge" for instruments. Americans often use "gage" for instruments.
See also adjusting gage, compression gage, dial gage, feeler gage, fuel gage, gas gage, oil gage, oil pressure gage, plain gage tubing, temperature gage, tire gage, vacuum gage