n. pl. cal·cu·li (-lī′) or cal·cu·lus·es
1. Medicine An abnormal concretion in the body, usually formed of mineral salts and found in the gallbladder, kidney, or urinary bladder, for example.
2. Dentistry See tartar.
a. The branch of mathematics that deals with limits and the differentiation and integration of functions of one or more variables.
b. A method of analysis or calculation using a special symbolic notation.
c. The combined mathematics of differential calculus and integral calculus.
4. A system or method of calculation: "[a] dazzling grasp of the nation's byzantine budget calculus" (David M. Alpern).
[Latin, small stone used in reckoning; see CALCULATE.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.