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 [kal´ku-lus] (pl. cal´culi) (L.)
an abnormal concretion, usually composed of mineral salts, occurring within the body, chiefly in hollow organs or their passages. Called also stone. See also kidney stone and gallstone. adj., adj cal´culous.
biliary calculus gallstone.
bladder calculus vesical calculus.
bronchial calculus broncholith.
calcium oxalate calculus oxalate calculus.
dental calculus a hard, stonelike concretion, varying in color from creamy yellow to black, that forms on the teeth or dental prostheses through calcification of dental plaque; it begins as a yellowish film formed of calcium phosphate and carbonate, food particles, and other organic matter that is deposited on the teeth by the saliva. It should be removed regularly by a dentist or dental hygienist; if neglected, it can cause bacteria to lodge between the gums and the teeth, causing gum infection, dental caries, loosening of the teeth, and other disorders. Called also tartar.
gastric calculus gastrolith.
intestinal calculus enterolith.
lung calculus a hard mass or concretion formed in the bronchi around a small center of inorganic material, or from calcified portions of lung tissue or adjacent lymph nodes. Called also pneumolith.
mammary calculus a concretion in one of the lactiferous ducts.
nasal calculus rhinolith.
oxalate calculus a hard urinary calculus of calcium oxalate; some are covered with minute sharp spines that may abrade the renal pelvic epithelium, and others are smooth. Called also calcium oxalate calculus.
phosphate calculus a urinary calculus composed of a phosphate along with calcium oxalate and ammonium urate; it may be hard, soft, or friable, and so large that it may fill the renal pelvis and calices.
prostatic calculus a concretion formed in the prostate, chiefly of calcium carbonate and phosphate. Called also prostatolith.
renal calculus kidney stone.
staghorn calculus a urinary calculus, usually a phosphate calculus, found in the renal pelvis and shaped like the antlers of a stag because it extends into multiple calices.
urate calculus uric acid calculus.
urethral calculus a urinary calculus in the urethra; symptoms vary according to the patient's sex and the site of lodgment.
uric acid calculus a hard, yellow or reddish-yellow urinary calculus formed from uric acid.
urinary calculus a calculus in any part of the urinary tract; it is vesical when lodged in the bladder and renal (see kidney stone) when in the renal pelvis. Common types named for their primary components are oxalate calculi, phosphate calculi, and uric acid calculi. Called also urolith.
uterine calculus any kind of concretion in the uterus, such as a calcified myoma. Called also hysterolith and uterolith.
vesical calculus a urinary calculus in the urinary bladder. Called also bladder calculus.


, gen. and pl.


(kal'kyū-lŭs, -lī),
A concretion formed in any part of the body, most commonly in the passages of the biliary and urinary tracts; usually composed of salts of inorganic or organic acids, or of other material such as cholesterol.
Synonym(s): stone (1)
[L. a pebble]


n. pl. calcu·li (-lī′) or calcu·luses
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.


Indurated, yellow-brown/black deposits on teeth formed by bacteria in dental plaques from mineralised calcium salts in saliva and subgingival transudates. 

A stone in the urinary tract.

An abnormal, often calcium-rich mass found in various tissues, seen by light microscopy.


Plural, calculi Dentistry Tartar Indurated, yellow–brown/black deposits on teeth formed by bacteria in dental plaques from mineralized calcium salts in saliva and subgingival transudates Kidneys A stone in the urinary tract. See Mulberry calculus, Staghorn calculus.


, pl. calculi (kal'kyū-lŭs, -lī)
A concretion formed in any part of the body, most commonly in the passages of the biliary and urinary tracts; usually composed of salts of inorganic or organic acids, or of other material such as cholesterol.
See also: dental calculus
Synonym(s): stone (1) .
[L. a pebble]


A stone of any kind formed abnormally in the body, mainly in the urinary system and the gall bladder. Calculi form in fluids in which high concentrations of chemical substances are dissolved. Their formation is encouraged by infection.

calculus (dental)



Any type of hard concretion (stone) in the body, but usually found in the gallbladder, pancreas and kidneys. They are formed by the accumulation of excess mineral salts and other organic material such as blood or mucous. Calculi (pl.) can cause problems by lodging in and obstructing the proper flow of fluids, such as bile to the intestines or urine to the bladder.


, pl. calculi (kal'kyū-lŭs, -lī)
1. Synonym(s): dental calculus.
2. Concretion formed in any part of the body, most commonly in passages of biliary and urinary tracts; usually composed of salts of inorganic or organic acids, or of other material such as cholesterol.
Synonym(s): stone (1) .
[L. a pebble]

Patient discussion about calculus

Q. Why do i get kidney stones? I am 38 and have had three stones pass so far. Is it the coffee, the meat, the stress, or the damned DNA?! My uncle is in his 50s and has passed over 30 stones!

A. Kidney stones are very common and even without the genetic or familial background people tend to get them. Of course, the more family predisposition you have, the higher are your chances of developing them, which is probably why you did. Also, a diet rich with dairy and calcium can cause your body to store excess calcium, that tends to calcify and create stones. Not drinking enough fluid is also one of the reasons.

Q. how do i cure tonsil stones (tonsiloth)?

A. There are very little literature about this subject, but I heard about treatment in which the crypts (deep and narrow grooves on the tongue in which the stones form) are burned with laser.

As far as I know these stones don't cause damage by themselves so it's not such a common treatment.

You may read more here:

Q. Would kidney stones affect a PSA reading? Would drinking lots of grapefruit juice affect a PSA reading? My husband's PSA reading jumped from a 4.2 to a 17 in @ 2 years' time. How can that be? This man takes all sorts of supplements and really watches his diet. He also takes good care of his body, and does NOT look or act 68.

A. You should get your parathyroid gland checked out. Your calcium level might be causing the kidney stones.

More discussions about calculus
References in periodicals archive ?
"Everything started four or five years ago at Stevens with Alexei and fellow founder Alex Myasnikov to help students succeed in calculus," Kaminski said.
The first three sessions compared calculus detection between the explorer and thin UI.
From the ablation test setup (a), the fiber (a 365 [micro]m core diameter fiber, S-LLF365 SureFlex Fiber, Boston Scientific Corporation, San Jose, CA, USA, delivers the laser pulse) was held vertically by a clamp, and its tip was in contact with the calculus phantom situated in a holder under the fiber.
A small calculus found near the orifice of salivary duct may also be removed after widening of the orifice with a lacrimal probe.
The size of the calculus and its location were both independent predictors for urological intervention.
Ross, "A brief history and exposition of the fundamental theory of fractional calculus," in Fractional Calculus and Its Applications, vol.
Shock wave lithotripsy of a parotid duct calculus. J Laryngol Otol 2002; 116 (1): 61-2.
plaque and calculus, their role in gingivitis and periodontitis and maintenance of oral hygiene.
By chapter 2, in which characters use a differential equation to estimate the increase in the zombie population, it's clear that Adams intends his hell-for-leather plot to be a skeleton he will flesh out with calculus lectures.
THE UK's leading sports development tour company, inspiresport - which organises trips for thousands of youngsters annually to clubs such as Real Madrid and Ajax Amsterdam - has been boosted by a multi-million pound investment from private equity fund manager Calculus Capital.
Urinary Calculus Disease: A study of 267 cases at Sir Ganga Ram Hospital, Lahore over 2 years.