Scamper, you scam merchant
Kiwi inquirer Mike Brooker probably wouldn't complain if someone said he'd been scampering (unless he's afraid of seeming undignified) but he probably would object if someone said he'd been running a scam. Yet historically, the two things mean much the same thing.
Scam is a piece of United States slang that entered world usage about the 1970s, but it came originally from England. Capt Francis Grose's 1811 Dictionary of the Vulgar Tongue defines scamp as "highwayman" and to scamper as "to run away hastily". Eric Partridge's Dictionary of Historical Slang gives the date 1781 for scamp with this meaning, and 1804-40 for the meaning "fraud".
Neither gives the origin, but Partridge notes scamper, "run hastily", from 1687, so there's a good chance that scamp came from scamper, not vice versa. (An interesting similarity exists with burgle burglar: the noun burglar came first and was "verbed" into burgle. Shove that one under the nose of anyone who complains about nouns being "verbed".)
To call someone a scamp these days means little or nothing; it has a genial ring to it. But scam is its direct descendant.
Mr Brooker also said scam "appears to mean a fraud but seems to be more specific than that".
Sorry, I'd say the opposite is now true. Scam is so overused that it can mean anything from "trickery" to "fraud" to "dubious display".
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