Tartar
Part of speech: noun
Definition: A red compound deposited during wine making; mostly potassium hydrogen tartrate - a source of cream of tartar. A hard yellow deposit on the teeth.
Calculus
Part of speech: noun
Definition: calculation, computationAny formal system in which symbolic expressions are manipulated according to fixed rules.Differential calculus and integral calculus considered as a single subject; analysis.A stony concretion that forms in a bodily organ.Deposits of calcium phosphate salts on teeth.A decision-making method, especially one appropriate for a specialised realm.
Example sentence: The standard high school curriculum traditionally has been focused towards physics and engineering. So calculus, differential equations, and linear algebra have always been the most emphasized, and for good reason - these are very important.