Glossary Entries
A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  ZCalculate  To compute; to perform the indicated operation(s). 
Calendar  A tabular arrangement of the days, weeks, and months of the year. 
Capacity  The maximum amount that can be contained by an object. Often refers to measurement of a liquid. The term volume may also be used when talking about capacity. 
Cardinal Number  A cardinal number denotes how many objects are in a set. 
Cardinal Principle  The concept that the last number counted represents the cardinality of a set. 
Cartesian Plane  The coordinate plane that is formed by a horizontal and vertical axis. They are often labeled the xaxis and yaxis respectively. 
Categorical Data  Data that can be classified by type. The data is typically represented using a bar graph, circle graph, or pictograph. An example might be colors or breed of cat. 
Celsius  A temperature measurement scale where 0° represents the freezing point of water and 100º represents the boiling point of water; formerly known as centigrade. 
Cent  A unit of money equal to one onehundredth of one dollar. 
Centigrade  (See Celsius) 
Centimeter  A metric unit of length which is equal to onehundredth of a meter. The abbreviation for centimeter is "cm." 
Central Angle  An angle whose vertex is at the center of a circle and whose sides contain radii of the circle. 
Central Tendencies  A number which in some way conveys the "center" or "middle" of a set of data. The most frequently used measures are the mean and the median. 
Certainty  An event that is certain to happen in a probability experiment. Example:Drawing an odd number when selecting one number from a bag containing 6 slips of paper with the numbers 1, 3, 5, 7, 9, and 11 on them 
Change  Money in the form of coins and/or dollars that is received when you purchase an item with more money than the item costs. 
Characteristic  A distinguishing trait, quality, property, or attribute. 
Chart  A diagram that illustrates information in the form of a table, graph, or picture. 
Chord  Any line segment that connects any two points on a circle. 
Circle  A circle is a planeclosed curve consisting of all points a fixed distance from a fixed point called its center. 
Circle Graph or Pie Graph  A graph in which the data is represented by sectors of a circle; the total of all the sectors should be 100% of the data. 
Circumference  The distance around a circle also known as the perimeter. It is calculated by multiplying the diameter of the circle by PI (3.14...). (i.e., C = " pi"d). 
Classify  To sort into categories or to arrange into groups by attribute(s). 
Classify Triangles  To categorize a triangle according to its angles (acute, obtuse, or right) or the lengths of its sides (equilateral, isosceles, or scalene). 
Closed Figure  A figure that starts and ends at the same point. 
Cluster  Data that are grouped together. 
Coefficient  A constant that multiplies a variable. Example: 3x + 4y = 14, 3 is the coefficient of x and 4 is the coefficient of y. 
Coin  A flat piece of metal issued by governmental authority as money. Examples: Pennies, nickels, dimes, quarters. 
Collection  An accumulation of objects gathered for study or comparison. 
Combination  A subset from a larger set that is considered without regard to the order of the items chosen.Example: The number of different committees of seven that can be chosen from a group of twentyone people. Also see the definition of "Permutations." 
Combine Like Terms  To simplify expressions by adding or subtracting like terms. 
Commission  Earnings based on the amount of total sales. 
Common Denominator  A whole number greater than zero that is a common multiple of each denominator in two or more fractions. Example: Common denominators for onesixth and threeeighths are 24, 36, and 48. 
Common Factor  A number, polynomial, or quantity that evenly divides into two or more numbers or algebraic expressions. Examples:5 is a common factor of 15 and 30.2x is a common factor of 4xy and 6x^{2}. 
Common Multiple  A common multiple is a whole number that is a multiple of two or more given numbers. Example: The common multiples of 2, 3, and 4 are 12, 24, 36, 48, ... 
Commutative Property  Changing the order of the addends does not change the sum. Changing the order of the factors does not change the product. Example: 15 + 9 = 9 + 15; 3 x 8 = 8 x 3. 
Commutative Property of Addition  A property of real numbers that states that the sum of two terms is unaffected by the order in which the terms are added; i.e., the sum remains the same. Example: 2 + 3.5 = 3.5 + (2). 
Commutative Property of Multiplication  A property of real numbers that states that the product of two factors is unaffected by the order in which they are multiplied; i.e., the product remains the same. Examples: 3 * 5 = 5 * 3 or 5 * x = x * 5. 
Compare  To state the similarities or differences between two or more numbers, objects, or figures by considering size, shape, odd, even, or other attributes. 
Compass  An instrument used to locate points at a given distance from a fixed point, and to describe circles and arcs. 
Compatible Numbers  Numbers that go together easily; a strategy often used to estimate sums, differences, products, and quotients. 
Compensation  A strategy that can be used for addition which usually involves increasing one addend while decreasing the other by the same amount. Example: When adding 46 + 38, add 2 to 38 to make 40 and take two away from 46, resulting in 44; then add 40 + 44 to get 84. 
Complementary Angles  Two angles whose measures have a sum of 90º. Example: 50º and 40º are complementary angles. 
Complex Numbers  Numbers that have the form a + bi where a and b are real numbers and i satisfies the equation i^{2} = 1. Multiplication is denoted by ( a + bi )( c + di ) = ( ac  bd ) + ( ad + bc ) i , and addition is denoted by ( a + bi ) + ( c + di ) = ( a + c ) + ( b + d ) i . 
Compose  Part of a process of grouping decomposed numbers into quantities that are easier to compute. 
Composite Number  A number greater than zero that can be divided by more than <b>one (1) and itself</b>. It is the opposite of a prime number. 9 is a composite number because it has three factors:1, 3, and 9 
Compound Event  A combination of two or more simple events (e.g., the probability of rolling a 2 or a 3 when tossing a number cube). 
Computation  The act or action of carrying out a series of operations. 
Compute  To find the numerical result by applying arithmetic operations. 
Concave Polygon  A polygon with one or more diagonals that have points outside the polygon. 
Concentric  Two shapes that have the same center point. 
Conclusion  An answer or solution arrived at through logical or mathematical reasoning. 
Cone  A threedimensional shape that has a base in the shape of a circle or oval and a profile in the shape of a triangle. The surface is formed by straight line segments which join points on the boundary of the base to a fixed point, called its vertex, not in the plane containing the base. 
Congruence  The relationship between two objects that have exactly the same size and shape. 
Congruent  Two or more figures having exactly the same shape and size; coinciding when superimposed. 
Conjecture (noun)  An educated guess. A mathematical statement, thought to be true, which has neither been proven nor refuted by counterexample. 
Conjecture (verb)  To make a prediction or a statement, based upon guesswork and thought to be true. 
Consecutive  Following one right after the other in order. Examples: 1, 2, 3, ... are consecutive positive integers and –2, 0, 2, 4, ... are consecutive even integers. 
Conservation of Numbers  An understanding that rearranging a group of objects does not affect its number. 
Constant  A quantity that does not change its value in a given expression or equation (e.g., In the expression 3s + 4, 3 and 4 are constants). 
Construction  A precise way of drawing that allows only two tools: the straightedge and compass; the compass establishes equidistance, and the straightedge establishes collinearity. 
Convert  To change the form, but not the value of a particular number or quantity. 
Convex Polygon  A polygon with all interior angles measuring less than 180º. All diagonals of a convex polygon are inside the figure. 
Coordinate Axes  The two intersecting perpendicular lines in a plane that form the four quadrants for locating points, given the ordered pair of the points; the axes are referred to as the xaxis and the yaxis.

Coordinate Geometry  The study of geometry using a coordinate plane.

Coordinate Grid  A twodimensional system in which the coordinates of a point are its distances from two intersecting, usually perpendicular, straight lines called axes.

Coordinate Plane  A plane containing a set of coordinate axes in which each point is located by a set of coordinates (x,y); the point of intersection of the axes is called the origin and has coordinates (0,0).

Coordinate System  (also called rectangular coordinate system)A method of representing points in the plane or in space by means of numbers; a point in a plane can be located by its distance from both a horizontal and a vertical line called the axes; the horizontal line is called the xaxis; the vertical line is called the yaxis; the pairs of numbers are called ordered pairs; the first number, called the xcoordinate, designates the distance along the horizontal axis; the second number, called the ycoordinate, designates the distance along the vertical axis; the point at which the two axes intersect has the coordinates (0,0) and is called the origin. for example, the usual Cartesian coordinates x, y in the plane.

Coordinates  Numbers that represent a point on a graph. The coordinates (6,8) would refer to a point with an X value of 6 and a Y value of 8.

Correlation  The amount of positive or negative relationship existing between two measures. For example, if the height and weight of a set of individuals were measured, it could be said that there is a positive correlation between height and weight if the data showed that larger weights tended to be paired with larger heights and smaller weights tended to be paired with smaller heights. The stronger those tendencies, the larger the measure of correlation.

Corresponding Angles  Any pair of angles on the same side of the transversal, one interior and one exterior, formed when two parallel lines are intersected by a transversal.

Corresponding Sides  Sides in the same relative position on two congruent or similar figures. The corresponding sides of congruent figures are equal and the corresponding sides of similar figures are proportional.

Cosine  Cos(q) is the x coordinate of the point on the unit circle so that the ray connecting the point with the origin makes an angle of q with the positive x axis. When q is an angle of a right triangle, then cos(q) is the ratio of the adjacent side with the hypotenuse.

Count  To name the numbers in order up to and including a given number. To determine the total number or amount, as in money. Example: Count to ten.

Count Back  A subtraction strategy of starting with the minuend and counting backward an amount equal to the amount of the subtrahend to arrive at the difference. 
Count On  An addition strategy of starting with one addend (usually the larger) and counting forward an amount equal to the other addend to arrive at the sum.

Counterexample  An example to show that a rule is not true for all numbers. Example:Show by counterexample that the commutative property does not work  45 does not equal 54.

Counting Numbers  All whole numbers greater than zero; also called natural numbers.

Cube (Factor)  When you multiply a number by itself two times in a row. Example: The cube of 2 is 2 x 2 x 2 or 8.

Cube (Shape)  A six sided shape in which all of the sides are squares. The six sides are congruent. Think about dice from a game. Those are two cubes.

Cubic Unit  A unit for measuring volume.

Cup  A customary unit used to measure capacity; 1 cup = 8 ounces.

Currency  The money of a country that circulates as a medium of exchange (e.g., coins, dollar bills, euros).

Customary System  A system of measurement used in the U.S. The system includes units for measuring length, capacity, and weight. Length (e.g., inch, foot, yard, mile). Mass (e.g., ounce, pound, ton). Capacity (fluid ounce, cup, pint, quart, gallon).

Customary Units  The units of measure used in the customary measurement system.

Cylinder  A threedimensional figure with two circular bases that are parallel and congruent.

Useful Reference Materials
Wikipedia:https://en.wikipedia.org/wiki/Fraction_%28mathematics%29
Encyclopædia Britannica:
http://www.britannica.com/topic/fraction
University of Delaware:
https://sites.google.com/a/udel.edu/fractions/