On this theme you know how screws have fixed threads and bolts have nuts? On McMaster you couldn't for a long time ever find carriage bolts, which can only ever be bolts, if you started looking for screws, whereas hex heads for example came up for screws or bolts. We think they may have subsequently relaxed this admirably rigorous commitment to nomenclature though have haven't checked very recently.
I of course learned this rigor he hard what when I'd go to our big university machine shop and ask the man on duty (to help noobs like me) for tin foil. "No". Then a long silence followed by, "you don't mean aluminum foil do you? If so why would you ask for tin foil".