Napier's bones

American  

noun

(used with a singular verb)

1. a form of multiplication table originally marked on sticks of bone or ivory that could be rearranged to carry out the operations of multiplication or division.

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Napier's bones British  

plural noun

1. a set of graduated rods formerly used for multiplication and division

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Etymology

Origin of Napier's bones

First recorded in 1650–60; after their developer, J. Napier

Example Sentences

Napier’s bones - a device to facilitate calculation invented by John Napier in the seventeenth century - are now unbreakable.

From The Guardian • Oct. 3, 2016

Jedediah Buxton will be forgotten; but Napier's bones will live.

From Table Talk Essays on Men and Manners by Hazlitt, William

In Hudibras: "A moon-dial, with Napier's bones, And several constellation stones."

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

Musical Examinations, blunders in, 164 Napier's bones, 38.

From Literary Blunders by Wheatley, Henry Benjamin