Tom, Dick, and Harry

The phrase "Tom, Dick and Harry" is a placeholder for multiple unspecified people; "Tom, Dick or Harry" plays the same role for one unspecified person. The phrase most commonly occurs as "every Tom, Dick and Harry", meaning everyone, and "any Tom, Dick or Harry", meaning anyone, although Brewer's Dictionary of Phrase and Fable defines the term to specify "a set of nobodies; persons of no note".

Similar expressions exist in other languages of the world, using commonly used first or last names. The phrase is used in numerous works of fiction.

The origin of the phrase is unknown. The earliest known citation is from the 17th-century English theologian John Owen who used the words in 1657. Owen told a governing body at Oxford University that "our critical situation and our common interests were discussed out of journals and newspapers by every Tom, Dick and Harry." Pairs of common male names, particularly Jack and Tom, Dick and Tom, or Tom and Tib, were often used generically in Elizabethan times. For example, a variation of the phrase can be found in Shakespeare’s Henry IV, Part 1 (1597): "I am sworn brother to a leash of Drawers, and can call them by their names, as Tom, Dicke, and Francis."

The phrase is a rhetorical device known as a tricolon. The most common form of tricolon in English is an ascending tricolon, and as such the names are always said in order of ascending syllable length. Other examples of this gradation include "tall, dark and handsome", "", "The Good, the Bad and the Ugly"; and so on.

English-speaking medical students use the phrase in memorizing the order of an artery, and a nerve, and the three tendons of the flexor retinaculum in the lower leg: the T, D, A, N and H of Tom, Dick and Harry correspond to tibialis posterior, flexor digitorum longus, posterior tibial artery, tibial nerve, and flexor hallucis longus. This mnemonic is used to remember the order of the tendons from anterior to posterior at the level of the medial malleolus just posterior to the malleolus.

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