The Supreme Court is currently arguing on what the definition of clothing is.  

The reason is straightforward enough—the outcome of Sandifer v. United States Steel Corporation will decide whether or not workers should be compensated for the time they spend putting on protective gear. On Monday the debate wandered into existential territory.  If these workers are to be compensated, should everyone be paid for the time they spend getting ready for work? What is the difference between work "clothing" and work "gear"? Is everything we wear considered clothing? What about eyeglasses and wristwatches?  Does Justice Scalia wear a toupee?

You can read the transcript, if you’re so inclined, in which Justice Sotomayor gives a much-needed voice to the jousters of America, and Scalia, who may or may not be bald, learns all about knife scabbards from attorney Eric Schnapper, who is representing the steel workers.

Mr. Schnapper: Workers wear tool belts. It's—one of the recurring—recurring issues that has come up in these cases are knife scabbards. We don't think anyone would, in ordinary parlance, call those things clothes. And we think that's the significant limitation on this. And so even though you could be wearing those things, those are not clothes.

Justice Scalia: Tools and what?

Mr. Schnapper: Scabbards.

Justice Scalia: Scabbards. 

If this whole debacle has got you itching to accessorize with a knife scabbard of your own, you can pick up an All-American one from L.L. Bean ($19.50) and let SCOTUS know whether you put it in your closet or your toolbox.