1. One that calculates, as:
   1. An electronic or mechanical device for the performance of mathematical computations.
   2. A person who operates such a machine or otherwise makes calculations.
2. A set of mathematical tables used to aid in calculating.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.