calculus calculus /ˈkælkjələs/

noun

1. () A hard lump produced by the concretion of mineral salts; found in hollow organs or ducts of the body  ( concretion , calculus )
   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
   renal calculi can be very painful
   
   
2. (mathematics) the branch of mathematics that is concerned with limits and with the differentiation and integration of functions  ( calculus , infinitesimal calculus )
   (mathematics) the branch of mathematics that is concerned with limits and with the differentiation and integration of functions
   
3. An incrustation that forms on the teeth and gums  ( calculus , tartar , tophus )
   an incrustation that forms on the teeth and gums