Q From Jim Marchant, California: What are the origins of the phrase Clean their clock? It produces a lot of hits on Google, and sportswriters are fond of it, but I don’t see anything about its pedigree.
A In American English, To clean someone’s clock means to trounce one’s opponents in a game (“We’ll clean the Dodgers’ clocks today”) or generally to inflict a severe reverse (“Republicans got their clocks cleaned in November’s elections”).
It became particularly popular from the 1990s on, but it’s possible to trace it back a surprisingly long way. The first example that I’ve come across is a baseball report in the Trenton Evening Times in July 1908: “It took the Thistles just one inning to clean the clocks of the Times boys.” The stronger sense is to give somebody a thrashing, as in Stephen King’s story The Ten O’Clock People: “If I blew some [smoke] in his face, I bet he’d come over the top and clean my clock for me.” It’s not obvious from the written history of the expression that this is the original meaning, though it’s more than likely.
To clean goes back a lot further. Jonathon Lighter’s Historical Dictionary of American Slang lists it from 1819 in the sense of vanquishing or drubbing. All the early examples are either clean out or clean off but by Mark Twain’s time it had reduced to just clean (“He went for ’em! And he cleaned ’em, too!” is in Roughing It, dated 1871). The slang use of clock to mean face may also be from the nineteenth century, though the first examples are contemporary with the 1908 Trenton report. (We British had dial with the same sense from a century earlier.) Around that time to fix someone’s clock in North America also meant to defeat somebody but in a more thorough way. However, to clock a man, meaning to hit him in the face, is recorded only from the 1930s.
As an intriguing aside, US railway slang used clean the clock (and also wipe the gauge) to mean that a driver brought his train to a sudden halt by applying the air brakes. The allusion is to the gauge that shows the air pressure. A sudden use of the brakes will cause the needle to swing right over, so figuratively cleaning the glass of the gauge. This is recorded only from the late 1920s, so quite how it fits into the history of the expression isn’t clear.