Try Our Apps


Avoid these words. Seriously.


[kal-kyuh-luh s] /ˈkæl kyə ləs/
noun, plural calculi
[kal-kyuh-lahy] /ˈkæl kyəˌlaɪ/ (Show IPA),
Mathematics. a method of calculation, especially one of several highly systematic methods of treating problems by a special system of algebraic notations, as differential or integral calculus.
Pathology. a stone, or concretion, formed in the gallbladder, kidneys, or other parts of the body.
Also called tartar. Dentistry. a hard, yellowish to brownish-black deposit on teeth formed largely through the mineralization of dead bacteria in dental plaques by the calcium salts in salivary secretions and subgingival transudates.
calculation; estimation or computation:
the calculus of political appeal.
Origin of calculus
1610-20; < Latin: pebble, small stone (used in reckoning), equivalent to calc- (stem of calx stone) + -ulus -ule Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
Cite This Source
Examples from the Web for calculi
Historical Examples
British Dictionary definitions for calculi


noun (pl) -luses
a branch of mathematics, developed independently by Newton and Leibniz. Both differential calculus and integral calculus are concerned with the effect on a function of an infinitesimal change in the independent variable as it tends to zero
any mathematical system of calculation involving the use of symbols
(logic) an uninterpreted formal system Compare formal language (sense 2)
(pathol) (pl) -li (-ˌlaɪ). a stonelike concretion of minerals and salts found in ducts or hollow organs of the body
Word Origin
C17: from Latin: pebble, stone used in reckoning, from calx small stone, counter
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
Cite This Source
Word Origin and History for calculi



1660s, from Latin calculus "reckoning, account," originally "pebble used as a reckoning counter," diminutive of calx (genitive calcis) "limestone" (see chalk (n.)). Modern mathematical sense is a shortening of differential calculus. Also used from 1732 to mean kidney stones, etc., then generally for "concretion occurring accidentally in the animal body," such as dental plaque. Related: Calculous (adj.).

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
calculi in Medicine

calculus cal·cu·lus (kāl'kyə-ləs)
n. pl. cal·cu·lus·es or cal·cu·li (-lī')

  1. An abnormal concretion in the body, usually formed of mineral salts and most commonly found in the gallbladder, kidney, or urinary bladder. Also called stone.

  2. Dental tartar.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
calculi in Science
Plural calculi (kāl'kyə-lī') or calculuses
  1. The branch of mathematics that deals with limits and the differentiation and integration of functions of one or more variables. See more at calculus of variations, differential calculus, integral calculus.

  2. A solid mass, usually composed of inorganic material, formed in a cavity or tissue of the body. Calculi are most commonly found in the gallbladder, kidney, or urinary bladder. Also called stone.

The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
calculi in Culture

calculus definition

The branch of mathematics, usually studied after algebra, that provides a natural method for describing gradual change.

Note: Most modern sciences use calculus.
The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source

Word of the Day

Nearby words for calculi

Difficulty index for calculus

Most English speakers likely know this word

Word Value for calculi

Scrabble Words With Friends