calculus

UK: /ˈkælkjʊləs/ US: /ˈkælkjələs/ ,(kal′kyə ləs)

Inflections of 'calculus' (n):

calculi

npl

calculuses

npl

WordReference Random House Learner's Dictionary of American English © 2025

cal•cu•lus /ˈkælkyələs/   n. [uncountable]

1. Mathematics a branch of mathematics that calculates amounts that change constantly:
   Calculus can help you figure out how fast an object falls.
2. Dentistry a hard, yellowish substance on teeth formed from dental plaque;
   tartar.

WordReference Random House Unabridged Dictionary of American English © 2025

cal•cu•lus  (kal′kyə ləs), n., pl. -li (-lī′), -lus•es. 

1. Mathematics a method of calculation, esp. one of several highly systematic methods of treating problems by a special system of algebraic notations, as differential or integral calculus.
2. Pathology a stone, or concretion, formed in the gallbladder, kidneys, or other parts of the body.
3. Dentistry Also called tartar. 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.
4. calculation:
   the calculus of political appeal.

• Latin: pebble, small stone (used in reckoning), equivalent. to calc- (stem of calx stone) + -ulus -ule
• 1610–20

calculus, +n. 

1. calculation:
   the calculus of political appeal.

Collins Concise English Dictionary © HarperCollins Publishers::

calculus / ˈkælkjʊləs/ noun ( -luses)

1. 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
2. any mathematical system of calculation involving the use of symbols
3. ( -li / -ˌlaɪ/) a stonelike concretion of minerals and salts found in ducts or hollow organs of the body

Etymology: 17th Century: from Latin: pebble, stone used in reckoning, from calx small stone, counter