MATH VOCABULARY
Intermediate
Acute Angle
An angle that measures less than a right angle (90°).
addend
Any of the numbers that are addedExample:2 + 3 = 5
The addends are 2 and 3.
A.M.
The time between midnight and noon
Angle
A figure formed by two rays that meet at a common endpoint
Area
The number of square units needed to cover a given surface.
ArrayAn arrangement that shows objects in rows and columns
Bar Graph
A way to show information that uses bars to stand for data
Benchmark
Numbers like 10, 25, 50, or 100 that are used to help make estimates
Calendar
A table that shows the days, weeks, and months of a year in order
Capacity
The amount a container can hold when filled
Cell
Any single box in a table
Circle Graph
A graph in the shape of a circle that shows data as a whole made up of different parts
Closed Figures
A shape that begins and ends at the same point
Cone
A solid, pointed figure that has a flat, round base
Congruent
Figures that have the same size and shape
These triangles are congruent.
Cube
A solid figure with six congruent square faces
Cumulative Frequency
A column in a table that keeps a running total in a frequency table
Cup
A customary unit used to measure capacity
2 cups = 1 pint
Cylinder
A solid figure that is shaped like a can
Decimal
A number that uses place value and a decimal point to show values less than
one, such as tenths and hundredths
3.47
Decimal point
A period used in decimal numbers to separate the whole number part from the
decimal part
Degree
A unit of measure used to measure parts of a circle. There are 360° in a circle.
Degree Celsius
A standard unit for measuring temperature in the metric system
Degrees Fahrenheit
A standard unit for measuring temperature in the
customary system
Denominator
The number below the bar in a fraction. It tells the total number of equal parts.
Diameter
A line segment that passes through the center of a circle and has its endpoints on
the circle
Difference
The answer in a subtraction problem
8 - 5 = 33 is the difference.
Dividend
The number that is being divided in a division problem
35 ÷ 5 = 7
The dividend is 35.
Divisor
The number that divides the dividend
18 ÷ 3 = 6
The divisor is 3.
Double bar graph
A graph using bars to compare similar kinds of data
Elapsed time
The time that passes from the start of an activity to the end of that activity
The elapsed time is one hour.
Equally likely
When the outcomes of an experiment have the same chance of happening
You are equally likely to roll 1, 2, 3, 4, 5, or 6.
Equilateral triangle
A triangle with all sides congruent
Equivalent decimals
Two or more decimals that name the same amount
0.3 and 0.30 name the same amount.
Equivalent fractions
Two or more fractions that name the same amount
Expanded form
A way to write numbers by showing the value of each digit
635 = 600 + 30 + 5
1,479 = 1,000 + 400 + 70 + 9
Expression
A part of a number sentence that combines numbers and operation signs
(12 – 4) – 3
Fact family
A set of related addition and subtraction or multiplication and division number
sentences
2 + 4 = 6 6 - 4 = 24 + 2 = 6 6 - 2 = 4
or3 X 6 = 18 18 ÷ 6 = 36 X 3 = 18 18 ÷ 3 = 6
Factor
A number that is multiplied by another number to find a product.
4
4 X 7 = 28 X 7
28
The factors are 4 and 7.
Factor tree
A diagram that shows the prime factors of a composite number
Fraction
A number that names part of a whole or part of a group
Frequency table
A table that organizes the total for each category or group
Gallon
A customary unit used to measure capacity
4 quarts = 1 gallon
Grouping property of addition
The property which states that the way addends are grouped does not change the sum
(5 + 9) + 3 = 5 + (9 + 3)14 + 3 = 5 + 12
17 = 17
Grouping property of multiplication
The property which states that the way factors are grouped does not change the
product
(2 X 3) X 4 = 2 X (3 X 4)
6 X 4 = 2 X 12
24 = 24
Hexagon
A polygon with 6 sides and 6 angles
Horizontal
The direction from left to right
Hundredth
One of one hundred equal parts
Impossible
Something that will never happen
Example:
A dinosaur will walk into your classroom today.
Intersecting lines
Two or more lines that cross at exactly one point
The lines intersect at point B
IntervalThe distance between the numbers on the
scale of a graph.
Inverse operations
Opposite operations that undo each other; Addition and subtraction are inverse
operations, and so are multiplication and division.
5 + 4 = 9, so 9 – 4 = 5
3 X 4 = 12, so 12 ÷ 4 = 3
Isosceles triangle
A triangle with two congruent sides
Line
A straight path extending in both directions with no endpoints
Line graph
A graph that uses line segments to show how data change over a period of time
Line plot
A diagram that shows the frequency of data as they are collected
Line segment
Part of a line, with two endpoints
Line symmetry
A figure has line symmetry when it can be folded about a line so that its two parts are
identical.
Linear unitsAn inch is about the length of your thumb from the first knuckle to the tip.
A foot is about the height of a cat.
A yard is about the length of a baseball bat.
A mile is about the distance you can walk in 20 minutes.
Mean
Step 1Use unit cubes. Make 6 stacks of cubes to model the number of tickets sold each day.
Step 2Arrange the stacks in order from the shortest to the tallest.
Step 3To find the mean, move the cubes so the 6 stacks are equal in height. The number of cubes in each stack is the mean.
median
The middle number in an ordered series of numbers
The median of 1, 3, 4, 6, and 7 is 4.
mode
The number that occurs most often in a list of data
The mode of 1, 3, 4, 4, and 6 is 4.
Multiple
Negative numbers
Numbers less than zero
Net
A two-dimensional pattern of a three-dimensional solid
Nominal
A number that names things
Numeration system
A way to count and name numbers
Numerator
The number above the bar in a fraction. It tells how many of the equal parts of the whole or group are being considered.
Obtuse angle
An angle whose measure is greater than 90° and less than 180°
octagon
A polygon with 8 sides and 8 angles
One-dimensional
A measure in only one direction, such as length
Open figure
A figure that does not begin and end at the same point
Opposites
1 and –1 3 and –3 7 and –7
Order property of multiplication
The property which states that when the order of the two factors is changed, the product is the
same
4 X 5 = 5 X 420 = 20
Ordered PairA pair of numbers used to locate a
point on a grid.
(1,2) represents 1 space to the right of zero and 2 spaces up.
Ordinal
A number that tells position or order
Jon won first place.
Jean is 4th in line.
Parallel lines
Lines that never cross and are always the same distance apart
Parallelogram
A quadrilateral with 2 pairs of parallel sides, 2 pairs of equal angles, and 2 pairs of
equal sides
Pentagon
A polygon with 5 sides and 5 angles
Perimeter
The distance around a figure
2 cm + 3 cm + 3 cm = 8 cmThe perimeter of this figure is 8 centimeters.
Period
Each group of three digits in a number
Perpendicular lines
Two lines that intersect to form four right angles
Pictograph
A graph that uses pictures to show and compare information
Pint
A customary unit used to measure capacity
2 cups = 1 pint
Place value
The system in which the position of a digit in a number determines its value; see
decimal number system
Plane
A flat surface that extends without end in all directions
Planes are named by three points in the plane.
Plane Figure
A figure that lies in one plane
P.M.
The time between noon and midnight
Point symmetry
When a figure can be turned about a central point and still look the same in at least two positions
ProbabilityThe chance that a given event will occur
Probability of red =1
4
Quart
A customary unit used to measure capacity
2 pints = 1 quart
Quotient
The answer in a division problem
35 ÷ 5 = 7 The quotient is 7.
Radius
A line segment with one endpoint at the center of a circle and the other endpoint
on the circle
Range
The difference between the greatest and the least numbers in a set of numbers
range: 6 – 0 = 6
Ray
A part of a line that begins at one endpoint and extends forever in only one direction
Rectangle
A polygon with 4 sides and 4 right angles
Rectangular prism
A solid figure in which all six faces are rectangles
Reflection (flip)
The result of a figure flipped over a line
Remainder
The amount left over when you find a quotient
Rhombus
A parallelogram whose four sides are congruent and whose opposite angles are
congruent
Right angle
An angle that forms a square corner and measures 90°
Rotation (turn)
The action of turning a figure around a point or a vertex
scale
A series of numbers placed at fixed distances on a graph to help label the
graph
Scalene triangle
A triangle in which each side has a different length
Schedule
A table that lists activities and the times they happen
FLIGHTS FROM MIAMI TONEW YORK CITY
Each flight lasts about 2 hoursand 45 minutes.
Airline Departure Time
Airline A 9:10 A.M.
Airline B 10:15 A.M.
Airline C 12:50 P.M.
Airline D 1:20 P.M.
Similar figures
Figures that have the same shape but may have different sizes
Simplest form
When a fraction can be modeled with the largest fraction bar possible
Solid figures
sphere
cube
cylinderrectangularprism
conesquarepyramid
square
A polygon with 4 equal sides and 4 right angles
Square pyramid
A solid figure with a base that is a square and four faces that are triangles
Tally table
A way to organize data that uses tally marks to show how often something happens
tangram
A puzzle consisting of seven polygon-shaped pieces that can be rearranged to
make various figures or shapes
tenth
One of ten equal parts
tessellation
A repeating pattern of closed figures that covers a surface with no gaps and no overlaps
Three-dimensional
A measure in three directions, such as length, width, and height
transformationThe movement of a figure, either a
translation, rotation, or reflection
Translation (slide)
The action of sliding a figure in any direction
trapezoid
A quadrilateral with only one pair of parallel sides
Tree diagram
An organized list that shows all possible outcomes of an event
So, there are 6 possible outcomes.
triangle
A polygon with 3 sides and 3 angles
24-hour clock
A clock that does not use A.M. or P.M.
Two-dimensional
A measure in two directions, such as length and width
Venn diagram
A diagram that uses circles to show relationships among sets of things
vertex
The point at which two rays of an angle or two or more line segments meet in a plane figure, or where three or more sides meet
in a solid figure
vertical
The direction from top to bottom
volume
The measure of the space a solid figure occupies
x-coordinate
The first number in an ordered pair
(4, 6) (2, 5)
y-coordinate
• (3, 7) (5, 9)
The second number in an ordered pair
Zero property for multiplication
The property which states that the product of zero and any number is zero
13 X 0 = 0
0 X 7 = 0