Examples:

calibrate  To divide or mark something, such as on a thermometer, with gradations.

calorie  A unit for the amount of energy a food will produce when it is digested by the body.

capacity  A measure of how much liquid or other pourable substance a container can hold.  See also volume.

cartographer  A map maker.

cell  In a spreadsheet, a box formed where a column and a row intersect.  A column is a section of cells lined up vertically.  A row is a section of cells lined up horizontally.

census  An official count of a population, usually including the collection of information such as age, sex, education, income, and so on.

center  See circle or sphere.

centimeter (cm)  In the metric system, a unit of length defined as 1/100 of a meter; equal to 10 millimeters or 1/10 of a decimeter.

chance  The possibility of an outcome in an uncertain event.  For example, in tossing a coin there is an equal chance of getting heads or tails.

circle  The set of all points in a plane that are a given distance (the radius) from a given point (the center of the circle).

circle graph  A graph in which a circle and its interior are divided into parts to represent the categories in a set of data.  The circle represents the whole set of data.  Also called a pie graph.

circumference  The distance around a circle or sphere.

clockwise  In the same direction as the hands of a clock rotate; to the right.

column  See cell.

combine like terms  See like terms.

common denominator  Any nonzero number that is a multiple of the denominators of two or more fractions.

common factor  Any number that is a factor of two or more numbers.

compass-and-straightedge construction  The drawing of geometric figures using only a compass and straightedge.

complementary angles  Two angles whose measures total 90°.

composite number  A whole number that has more than two whole-number factors.  For example, 10 is a composite number because it has more than two factors: 1, 2, 5, and 10.  A composite number is divisible by at least three whole numbers.  See also prime number.

compound unit  A quotient or product of units of measure.  For example, miles per hour (mi/hr, mph) and square centimeters (cm²) are compound units.

concave (nonconvex) polygon  A polygon in which at least one vertex is “pushed in.”  A line may intersect a concave polygon at more than two points.

concentric circles  Circles that have the same center but radiuses of different lengths.

cone  A 3-dimensional shape having a circular base, curved surface, and one vertex.

congruent  Two figures that have identical sizes and shapes.  Congruent figures are said to be congruent to each other.  In the figures in the margin, the congruent sides are marked with the same number of slashes.  The symbol @ means “is congruent to.”

consecutive  Following one another in an uninterrupted order.  For example, A, B, C, and D are four consecutive letters of the alphabet; 6, 7, 8, 9, and 10 are five consecutive whole numbers.

consecutive angles  Angles in a polygon or polyhedron that share a common side.

constant  A number used over and over with an operation performed on many numbers.

constant term  See term.

contour line  A curve through places on a map where a measurement (for example, temperature, elevation, or length of growing season) is the same.

conversion fact  A relationship such as 1 yard = 3 feet or 1 gallon = 4 quarts.  A rate equal to 1 used to convert a quantity with one unit to a quantity with another unit.

convex polygon  A polygon in which all vertices are “pushed outward.”  A line can intersect a convex polygon at not more than two points.

coordinate  A number used to locate a point on a number line, or either of two numbers used to locate a point on a coordinate grid.  See also ordered number pair.

coordinate grid  A device for locating points in a plane by means of ordered number pairs or coordinates.  A coordinate grid is formed by two number lines that intersect at right angles at their 0 points.

corresponding sides  Two sides in the same relative position in two figures.  In the diagram in the margin, corresponding sides are marked with the same number of slash marks.

counterclockwise  Opposite to the direction in which the hands of a clock rotate; to the left.

counting numbers  The numbers used to count things; the set of counting numbers is {1, 2, 3, 4, … }.  All counting numbers are integers and rational numbers, but not all integers or rational numbers are counting numbers.  Also called natural numbers.  The counting numbers and 0 are called whole numbers.

cover-up method  A method for finding the solution of an equation by covering up a part of the equation containing a variable.

credit  An amount, such as a deposit, added to a bank balance.

cross section  A shape formed by the intersection of a plane and a geometric solid.

cube  See regular polyhedron.

cube of a number  The product of a number used as a factor three time.  For example, the cube of 5 is 5 * 5 * 5 = 5³ = 125.

cubic centimeter (cm³)  A metric unit of volume; the volume of a cube 1 centimeter on an edge.  1 cubic centimeter is equal to 1 milliliter.

cubic unit  A unit used in a volume and capacity measurement.

cubit  An ancient unit of length, measured from the point of the elbow to the end of the middle finger, or about 18 inches.  The Latin word cubitum means “elbow.”

curved surface  A surface that is rounded rather than flat.

customary system of measurement  The measuring system used most often in the United States.  Units for linear measure (length, distance) include inch, foot, yard, and mile; units for weight include ounce and pound; units for capacity (amount of liquid or other pourable substance a container can hold) include fluid ounce, cup, pint, quart, and gallon.

cylinder  A 3-dimensional shape having a curved surface and parallel circular or elliptical bases that are congruent.  A can is a common object with a cylindrical shape.