Portable holes and dop kits and duffles

The local daily published a commemoration of the post-WWII polio epidemic. An iron lung was mentioned as having "portable holes." This must have been seen by a lot of eyes before it made print. And now nobody knows about Dopp kits. And duffel coats and duffel bags are fading from common knowledge. And very soon the last of those who know the difference will have been translated to other planes of existence.