Stocks and stores. Basically, stocks are collections of materials, and stores are places to keep them in. Trickiness arises from people's tendency to use the word for what is contained as the name of the container itself - and vice-versa. For example, when someone asks if the kettle has boiled, they don't really mean the "varná kanvica" but the water inside it.

When someone asks if some material is "in stock", it sounds like they're asking if it's in the place, but in fact they just want to know if there's any available. The confusion is compounded by the Slovak expression "na sklade". Another meaning of stock is "balík akcií" at the stock exchange, representing investments in joint-stock companies ("akciové spoločnosti"). Another meaning of "store" is "shop", as in "department store" like Tesco on Main Street.