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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.
3. Mathematics
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.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
Bladder calculi have always presented problems with treatment secondary to their large size (see Figures 1 & 2).
More precisely, there exists an isomorphism between the kernel of [Lambda.sub.c] and suitably "shrunk" versions of each of the target calculi. It turns out that the dubious rules (let.1) and (let.2) have a natural interpretation as administrative reductions (that is, they can be viewed as occurring at compile time rather than run time), which makes them far more intuitive: they correspond to the naming of subterms, which is considered one of the beneficial properties of CPS.
"I am a T4 paraplegic, recently diagnosed with renal calculi. What does this mean?"
We need many levels of explanation: many different languages, calculi, and theories for the different specialisms.
Objective: To evaluate the therapeutic effects of visual standard channel combined with F4.8 visual puncture super-mini percutaneous nephrolithotomy (SMP) on multiple renal calculi.
PCNL is a well-established treatment option for patients with large and complex renal calculi. The overall complication rate of PCNL can be up to 83%, which can be minimised by accurate patient selection and careful postoperative follow-up [1].
[2] Renal calculi may descend into the urinary bladder and attain a larger size owing to deposition of phosphates.
Objective: To compare the therapeutic effects of visual standard channel combined with visual superfine precision puncture channel or super-mini percutaneous nephrolithotomy (PCNL) on multiple renal calculi.
Thin-section unenhanced abdominal CT is regarded as the gold standard imaging modality for the diagnosis of urinary system calculi due to high specificity and sensitivity vaiues (2).
Calculi occur in the urinary tract (kidney, ureter, bladder, and urethra) affecting about 10% of the population with a high recurrence rate of ~50% [1-4].
Symptomatic and obstructive calculi of the prostatic urethra are an uncommon clinical entity.
Results: Urinalysis was identified as an invalid indicator for renal tract calculi in patients with acute flank pain.