For that matter, why do we even call food and household supplies "groceries"?
It's interesting to see what other languages literally call their weekly visit to the supermarket:
French: épicerie (spices)
Dutch: krudenierswaren (herb/spice seller's wares)
Spanish: comestibles (edibles)
Italian: generi alimentari (food types)
German: Lebensmittel (means of life)
and for the Danes, apparently, a weekly shop is not enough, because they buy
daglig varer (daily goods)
But we English speakers like to buy in bulk, it would seem, for this is the origin of the word "grocery", which ultimately derives from the French word gros (big) and the Latin word grossus (thick). Here are the Oxford English Dictionary's definitions for "grocer":
One who buys and sells in the gross, i.e. in large quantities, a wholesale dealer or merchant [in contrast to a retailer, for which see this post]; also with mention of the article dealt in, e.g. fish. (The company of Grocers, said to have been incorporated in 1344, consisted of wholesale dealers in spices and foreign produce),
A trader who deals in spices [you see now where the French and Dutch got their word from], dried fruits, sugar, and, in general, all articles of domestic consumption except those that are considered the distinctive wares of some other class of tradesmen. In 18–19th c. tea, coffee, and cocoa became characteristic articles of the grocer's trade. After 1860 many grocers held licences to sell beer, wines, and spirits, in bottles.
"Grocery" was originally a collective noun for all such wares (as épicerie still is in French):
1660 F. Brooke tr. V. Le Blanc World Surveyed 47 Confections, and preserves, of all sorts, spices, and all sorts of grocery come from China.
But because (unlike my single-loaf-buying friend) one usually buys more than one such item at a time, the plural "groceries" also started to be used, and finally won out.
The shop where you buy your "means of life" started to be called a "grocery (store)" in the early 19th century in North America, and this usage is still more common here than in the UK, where they are more likely to say "(green)grocer's". Beware, though, if reading older texts from the southern US, that "grocery" often meant "liquor store"!
Another interesting point about these words is the pronunciation. Some people in North America (including my friend who initiated this post) say "grow-sher(ee)" rather than "grow-sser(ee)". This is a natural phonetic phenomenon caused by the proximity of the "r" to the "s". I was quite surprised to hear it when I first moved to Ontario, but we did a survey for the Canadian Oxford Dictionary and found it was quite common. Our dictionary and some American dictionaries include it. What do you say?
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