The Guardian was discussing the effect on British stores of the takeover of the British supermarket chain Asda by Wal-Mart. “Defensive action,” it said, “saw the cost of staple goods such as cereals, chips and ice cream slump in September”.
These consumables (foodstuffs hardly seems the right word) can’t be called staples in the usual sense, which is usually confined to indispensable items like bread. But not for the supermarkets, it seems; they don’t make much money on such essentials, as they price them competitively if not actually as loss leaders. Their profit margins are much better on the goods we like but don’t really need, such as ice cream. The writer was presumably implying that these are staple goods for the supermarkets because they’re the ones they make their money on, or at least used to.
It’s all a long way from the origins of this word. A staple had nothing to do with food, and wasn’t even a thing, but a place. It was Edward II — or more probably his advisers — who had the neat idea that the way to stop merchants cheating the Exchequer out of taxes was to make them all trade in one place, where it was easy to keep an eye on them. England’s biggest trade good at the time was wool, which was sold on in its raw state to weavers in Flanders. A good location to make the middlemen congregate was Calais, then a British possession. This became The Staple from about 1390 to 1558.
Why staple? That’s not entirely clear. There was an ancient German word that meant a pillar, which became the source for the Middle Low German and Middle Dutch word stapel for a market or shop. It’s just a guess, but it may have happened through an association of ideas, a town market often being held under the pillars of a market hall. On the other hand, modern German and Dutch have the word stapel for a pile or heap, so the association may be with goods stacked up ready for inspection and sale. However it originated, the word came into English through the Old French estaple and was given to the trading fairs held at Calais, and also to some in other big towns throughout Britain, for example the gigantic one on St Giles Hill at Winchester each September.
A staple was always held under the command of the king, who appointed officials to ensure trade was done according to the rules, that quality was maintained and — especially — that he got his cut. Because of the great importance of wool, the merchants trading in it became known as staplers.
It’s not surprising that staple moved from describing the place where trade took place to the principal goods bought and sold there. Apart from wool — and woollen cloth — leather, tin, and some other goods were included at various times. Down the years, the word came to mean any item of special importance, whether of trade or of diet.
The other main meaning of staple, of a bent metal fastener, may seem to have nothing whatever to do with all this. But it’s thought the two words come from the same source, though it’s even less clear how an ancient word for a pillar became something we use to clip papers together. Perhaps early examples — which resembled croquet hoops more than paper fasteners — looked like a miniature pair of pillars. Who knows?