The seven-year itch
The inclination to become unfaithful after seven years of marriage.
The Seven Year Itch is best-known to us as the title of the 1955 film, starring Marilyn Monroe and Tom Ewell and directed by Billy Wilder. The plot of has Ewell's character working for a company that is about to publish a book suggesting that a many men have extra-marital affairs after seven years of marriage - called the "7-Year Itch". The film contains one of the most famous images in cinema history - Monroe's dress blowing up over a subway grating. That supposed urge for infidelity after seven years of marriage is the meaning we now have for this phrase. It is now often extended to refer to an urge to move on from any situation, and not even limited to those of seven years' duration.
George Axelrod, who wrote the play on which the film was based, didn't coin the phrase though. It came from an earlier US source. The original seven-year itch wasn't a condition that supposedly began after seven years, but one that supposedly lasted for seven years. Seven-year itch had been known in the USA since the early 19th century as the name of a particularly irritating and contagious skin complaint. The name was well enough known by 1845 for the condition to be used as a metaphor for all that is annoying; for example, this item from that year, from the Wisconsin Herald and Grant County Advertiser:
"When Illinois caught Mormonism off Missouri, she caught something worse than the seven year itch. Job sitting in the ashes and scratching himself amongst the potsherds, was infinitely more comfortable than poor Illinois now is, burning and festering under the scab of Mormonism."
The condition, which was bacterial in nature - causing highly irritating red pimples on the face and body, is now so easily treated as to have been virtually forgotten. In the 19th and early 20th centuries though it was viewed as being so bad that it was used as an appropriate imagined punishment for antisocial behaviour - "he should be given the seven-year itch and not be allowed to scratch". The difficulty of getting any relief from the condition was also expressed in the simile - "as close as the seven-year itch".
In a sad parallel of more recent criminal cases involving people who have been maliciously infected with the HIV virus (called 'revenge sex'), the Iowa State Press reported this in November 1903:
"Brahm vs. Corey - an action brought by the plaintiff to recover damages because of an attack of the 'seven year itch'. A contagious disease which, it is claimed, was communicated purposely by the plaintiff to he defendant."
The complaint was also known as camp itch or army itch and was associated with the US army where, around the turn of the 20th century, it was considered to be so rife that civilians would cross the street to avoid being near soldiers. Following discharge from the army in Europe after WWI many soldiers made their way to Paris, where the condition spread, under the pseudonym of French itch.
Relief was at hand though. By 1920 adverts like this were appearing in US newspapers and subsequently printed records that refer to seven-year itch diminished, until the 1955 film was released and the term began a new life.
See other phrases that were coined in the USA.