noun (used with a singular verb) Mathematics.
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.
Origin of Napier's bones
First recorded in 1650–60; after their developer, J. Napier
Also called Napier's rods.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for napier's bones
a set of graduated rods formerly used for multiplication and division
Word Origin for Napier's bones
C17: based on a method invented by John Napier
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012