Now are you talking about archaic words and phrases used in an older time where they were more universally used, but now have more specialized meanings? There is one word to me that comes to mind we all know very well: Typewriter. It once not only referenced a machine that prints letters, numbers, and characters on a page, it also denoted the operator of said machine. Later on, I'm not sure when, but "typewriter," in reference to the operator, was changed to "typist." Typing, a verb describing the use of a typewriter, also is used in sorting, say, blood or tissue. Today, it is used for the latter definition a little more, since typing as a means of communication has been substituted with "keyboarding." Students don't take "Typing class," anymore, but "Keyboarding class." It is doubtful that anymore than a mere handful of these students have ever seen a typewriter. Which is why it is very important for each of us to preserve as any extant typewriters as we can, so that this part of our history will still be available to learn.