The word “gauge” plays several roles. It both measures something and is the measure of something.
A speedometer, for example, is one “gauge” on your dashboard. It “gauges,” or measures, your speed.
But in a shotgun, the “gauge” is the size of its barrel, or of the shell that fits that barrel. It is a measurement unto itself.
On the dashboard “gauge,” the higher the number, the greater your speed. But when measuring the “gauge” of a shotgun barrel, or the thickness of a wire, larger numbers indicate a smaller measurement: A 30-gauge wire is thinner than a 20-gauge wire. That’s because the measurement of a wire was based on the number of times it had to be passed through the process that made it thinner, known as the “drawing” of wire. The more passes, the thinner the wire, and the higher the “gauge.”
That means it’s better to not call something “small,” “low,” “high,” or “large” when it’s measured by its “gauge”: To those who don’t know any better, a “small-gauge shotgun” may evoke the image of a barrel with a small diameter, when in fact, it’s quite large. (To make matters worse, the “gauge” in firearms is also known as the “bore,” and “bore” also refers to the surface of the inside of a barrel. But let’s not get bored here.) Instead, say something is “thin” or “thick,” or better yet, give the actual “gauge.”
Sometimes, “gauge” is spelled “guage,” but that’s usually either a typo or a mistaken belief that since the last syllable of “language” is spelled that way, so should “gauge.” Even if they sound nothing alike.
Most spelling checkers will point “guage” out to you, but if you spell it “gage,” they’ll sail right on by. That’s because “gage” can be correct, but probably not the way you mean.
Engineers might use a “strain gage,” also known as an “extensometer” to measure, um, strain on something, such as tension on a bridge. “Strain gauge” is correct, too. “Gage” is a “variant spelling” of “gauge,” meaning one that’s disputed but common.
But “gage” is also a real word of its own: It’s a token to guarantee that a promise or obligation will be fulfilled. When you pawn something, or put it on layaway, the item is the “gage” that you’ll be back to fulfill payment and claim the item. “Gage” is etymologically related to “wed,” which originally meant a pledge to fulfill an obligation. (Wish we’d known that when we wrote about marriage a few weeks ago!)
Webster’s New World College Dictionary says a gage is also “a pledge to appear and fight, as a glove thrown down by a knight challenging another.”
Wait, you say. Isn’t that glove called a “gauntlet”? Well, yes. The “gauntlet” is what is thrown down to make the challenge; when it’s picked up by the intended opponent, it’s transformed into a “gage.”
And while we’re on “gauntlet,” one “gauge” of how precise you are about language is what you call an ordeal like forcing someone to run between two lines of people as he’s being paddled on both sides. If you call it a “gauntlet,” some will say you’re wrong. That kind of punishment is really a “gantlet,” though Garner’s Modern American Usage says “gauntlet” has become correct everywhere but in the halls of “proper” usage.
Another “gantlet,” WNW says, is “a section of railroad track through a narrow passage where two lines of track overlap, one rail of each line being within the rails of the other.” It doesn’t matter whether it’s a narrow “gauge” railroad or not; it’s still a “gantlet.”