The word entered English in the 1620s, from Latin. Samuel Purchas used an early form of it in 1613, in his travel narrative Pilgrimage, for a man stolen away from his friends as a child.
Latin gave the word to English. The Roman poet Martial used its earliest sense as a joke, in a book of epigrams published around AD 86, comparing one kind of offence to another. English writers did not pick up his joke until the end of the sixteenth century.
Behind the English word was a Latin word that named a person who abducts the child or slave of another. And behind this word lay either an older Latin word for a hunting net, or a Greek word meaning oblique, or slanting.
PLACENTA and PLAGAL share the same distant root. PLACENTA entered English in 1559, from Latin, and was named after a kind of flat Roman cake, since the organ was thought to resemble one in shape. PLAGAL entered English in 1597, in the composer Thomas Morley's Plaine and Easie Introduction to Musicke, naming a family of church modes that sit a musical interval called a fourth below their partner scales. Both trace to an ancient root meaning simply flat, or spread out.
By the eighteenth century the word had settled fully into its modern sense. Sir Isaac Newton spent years accusing the German mathematician Gottfried Leibniz of exactly this, insisting he alone had invented calculus. Samuel Johnson, writing in his periodical The Idler in 1759, complained that writers who merely copied and repackaged old material were rewarded far too well.
