[1] : The Collaborative International Dictionary of English v.0.48

napier's bones \na"pier's bones`\, napier's rods \na"pier's
rods`\
   a set of rods, made of bone or other material, each divided
   into nine spaces, and containing the numbers of a column of
   the multiplication table; -- a contrivance of baron napier,
   the inventor of logarithms, for facilitating the operations
   of multiplication and division.
   1913 webster

[2] : WordNet (r) 2.0

napier's bones
     n : a set of graduated rods formerly used to do multiplication
         and division by a method invented by john napier syn: napier's
         rods
see also:
napier's rods 

Napiers Bones >> N Words
Napiers Bones, definition of term: Napiers Bones
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Bones >> B Words
Bones, definition of term: Bones
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