Q From John D Arnold: Do you know the provenance of the idiom to set one’s cap for someone or something?
A It’s often set one’s cap at, though both forms now feel rather dated. The idiom conventionally refers to a woman who sets out to gain the affections of a man, often with a view to marriage. The idiom starts to appear in the middle of the eighteenth century:
She was never known to set her Cap at any Man, and her Conversation is always so negligently sensible, that she cannot be suspected of studying to be brilliant, and if she captivates every Heart, it is without any premeditated Design.
The Gray’s Inn Journal, 5 Jan. 1754.
It has been suggested by at least one writer that the phrase was borrowed from the French expression mettre le cap sur. Today, that has the sense of “head for”, “set out for”, but in the eighteenth century it was specifically a seafaring idiom meaning to set course for some place.
We may imagine some young woman of the period, determined to marry well, aiming herself like a ship in full sail at the eligible bachelors of her acquaintance. Unfortunately for that fantasy, nobody has found any link between the French and English terms and none of the early examples of the idiom have nautical associations. The supposed connection seems to be based principally on cap appearing in both versions.
It’s much more likely that it derives from the conventional female dress of the period. At that time, unmarried young women would have worn a lace cap in public. When at an entertainment where she might meet an eligible male, she would naturally have worn her best clothes, including her cap. This is hinted at in this comment by Miss Kate Hardcastle to her father on the matter of a suitor, Mr Marlow:
My dear papa, why will you mortify one so? — Well, if he refuses, instead of breaking my heart at his indifference, I'll only break my glass for its flattery, set my cap to some newer fashion, and look out for some less difficult admirer.
She Stoops To Conquer, by Oliver Goldsmith, 1773.
The idiom remained common throughout the nineteenth century, used by Jane Austen, Charles Dickens, Anthony Trollope and others. American authors have also used it, though it has remained mainly a British idiom.
There were signs early in the nineteenth century that it was becoming unisex and was broadening its sense to refer to trying for some goal:
So the Rev. Mr. Begg of Paisley is leaving his good folks at last for the parish of Libberton. The minister of Libberton appeared just a-dying, and he [Mr Begg] began to set his cap at it.
The Reformers’ Gazette, 31 Jan. 1835.
By the end of the century, a gentleman setting his cap at some objective was no longer unusual, the cap having become so figurative that no image of maidenly lace was evoked. That is still true, as in this reference to the late John Updike:
But from earliest adolescence, he set his cap at The New Yorker as the summum of American literary production; and by the tender age of 22 he attained his goal.
Newsweek, 9 Feb. 2009. Summum: Latin for highest or greatest.