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

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

From Literary Blunders by Wheatley, Henry Benjamin

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