Q: I am given to understand that what is referred to as a “line” of people in the US is called a “queue” in the UK, though both Americans and British use “queue” the same way in its computer sense. How did all this come about?
A: Broadly speaking, you’re right—people ranked in an orderly sequence and waiting for something will be called a “line” in the US and a “queue” in the UK.
In Britain, violators who don’t take their turn are “jumping (or barging) the queue.” In North America, those who cheat are “cutting in line.”
However, the division between “line” and “queue” isn’t as clear as all that. The British used “line” for “queue” in the distant past, and some Americans have begun to use “queue,” probably influenced by British usage rather than by computer terminology.
But how did that broad general rule come to pass? Here’s the story.
“Line” is an extremely old word, dating back as far as the 600s in Old English. This word, like the equally ancient “linen,” has its source in the Latin linum (flax), and the earliest sense of “line” was flax—either spun into thread or woven into cloth.
So etymologically, a “line” is a linen thread. Even in Latin, the word linea (line), a derivative of linum, originally meant a linen thread, according to the Oxford English Dictionary.
Later senses of the word in English preserved this notion of a “line” as something stringlike—a narrow mark resembling a long string; a row of letters set into type; a string of objects or people, and so on.
The written use of “line” to mean a row of people dates to the late 16th century, the OED notes.
Shakespeare used “line” this way in Macbeth (circa 1606) in reference to a procession of ghostly kings: “What will the Line stretch out to’ th’ cracke of Doome?”
This sense of the word persists in American English, but the British replaced it in the 19th century with “queue,” a French word that originally meant “tail” and has roots in the Latin cauda (tail).
In English, “queue” didn’t originally mean a line of people. It was used in the 1400s to mean a band of parchment or vellum attached to a letter, according to the Chambers Dictionary of Etymology.
And in the 1500s, as John Ayto writes in his Dictionary of Word Origins, “queue” appeared in descriptions of heraldic shields and meant the tail of a beast.
Imaginative metaphorical uses appeared in the 1700s, etymologists say, when the word came to mean a braid (or “pigtail”), and a billiard stick (spelled “cue”).
Meanwhile, the French too were using their word queue in imaginative ways. In the 1790s, the OED says, French speakers began using queue to mean a “line or sequence of people waiting their turn to proceed or to be attended to.”
This usage leaped across the Channel in the following century. The OED’s earliest written example in English is from Thomas Carlyle’s The French Revolution (1837):
“That talent … of spontaneously standing in queue, distinguishes … the French People.”
Oxford says this use of “queue” is “chiefly British,” and the Dictionary of Word Origins says it “has never caught on in American English.” That explains why Chicagoans stand in a “line” while Liverpudlians form a “queue.”
The Americans, of course, are “lining” up. But how is the British participle spelled? Both “queuing” and “queueing” are correct, according to Fowler’s Modern English Usage (rev. 3rd ed.).
[Update, Dec. 16, 2014. A reader from New Zealand writes to comment: “Here in NZ, and I suspect the UK, we use both ‘queue’ and ‘line (up).’ While obviously related, there is a distinct difference between the two. We ‘queue’ as a way for many people to wait to receive service in an orderly fashion, while we ‘line up’ in order to proceed as a structured group. So we ‘queue’ to make a deposit at a bank, but we ‘line up’ to enter a classroom or to begin a parade. ‘Queue’ implies waiting your turn, while ‘line up’ implies organising prior to moving as a unit.”]
As for the computer sense of “queue,” the OED defines it as “a list of data items, commands, etc. stored so as to be retrievable in a definite order, usually the order of insertion.”
However, the earliest citation in the dictionary (from Automatic Data Processing, a 1963 book by F. P. Brooks and K. E. Iverson) refers to a queue in which the items are retrievable in the reverse order of insertion:
“The queue of components in the pool therefore obeys a so-called last-in-first-out, or LIFO discipline.”
[Update, Jan. 12, 2015. A reader notes that the Brooks and Iverson citation “was written in 1963 when dinosaurs roamed the earth and the terminology was still in a state of flux. What they describe as a ‘queue’ is what we would call a ‘stack’ in today’s jargon.”]