- calculus, concretion - a hard lump produced by the concretion of mineral salts; found in hollow organs or ducts of the body; "renal calculi can be very painful"
 --1 is a kind of rock, stone
 --1 has particulars:bladder stone, cystolith; enterolith; gallstone, bilestone; kidney stone, urinary calculus, nephrolith, renal calculus; ptyalith; sialolith, salivary calculus; urolith 
- tartar, calculus, tophus - an incrustation that forms on the teeth and gums
 --2 is a kind of crust, incrustation, encrustation
 
- calculus, the calculus, infinitesimal calculus - the branch of mathematics that is concerned with limits and with the differentiation and integration of functions
 --3 is a kind of pure mathematics
 --3 has particulars:analysis; differential calculus, method of fluxions; integral calculus; calculus of variations Derived form: verb calculate1