All SAT math terms

Glossary of 99 terms you need to read SAT Math questions clearly—definitions, examples, and category tags.

Show in glossary:

Absolute Value
Algebra
Definition
Distance from zero. The absolute value can never be negative.
Example
“|-17| = 17 and |42| = 42”
Arc
Geometry
Definition
A portion of the circumference of a circle. If the circle was a pizza, your slice would be a sector, and the crust on your slice would be an arc.
Example
“The curved edge of a pizza slice”
Base
Geometry
Definition
The bottom (and sometimes the top) of a 3-D geometric figure.
Example
“The base of a cylinder is a circle”
Box
Geometry
Definition
A 3-D figure with a length, width, and height, and where all the angles are right. This is also called a rectangular prism, and, if the three dimensions are all equal, it is a cube.
Example
“A shoebox or dice”
Circle
Geometry
Definition
The set of all points in a plane that are equidistant from a given point (aka, the center). A point is on the circle if it is on the circumference. A point is in the circle if it is in the area enclosed by the circumference.
Example
“A perfect round shape”
Center of a Circle
Geometry
Definition
The point from which all points on a circle are equidistant. The center is in the circle, but not on the circle. All the radii start at the center, and the center is the midpoint of every diameter.
Example
“The middle point of a circle”
Complex Number
Algebra
Definition
A number that is a mix of the real and the imaginary. It is given in the form a + bi, where a is the real part and bi is the imaginary part.
Example
“3 + 4i”
Cone
Geometry
Definition
A 3-D shape with a circular base on the bottom and a point on the top. A right circular cone means the point is directly above (or directly below) the center of the circular base.
Example
“An ice cream cone”
Confidence Interval
Statistics
Definition
A way to describe the level of uncertainty when a statistic about a population is being estimated by a sampling from that population. The confidence interval gives an upper and lower boundary between which you are a certain percent sure the true value falls.
Example
“Amy polled 100 people and asked them how they would vote in next week's election. 52% of them said they would vote for her. As a result, she is 90% sure that she will get between 47% and 57% of the vote on election day.”
Conjugates
Algebra
Definition
Two binomials in the form (a + b)(a - b). When you multiply conjugates, you will get a difference of squares. When you multiply complex conjugates (a + bi)(a - bi), you will magically turn something imaginary into something real!
Example
“(x + 3)(x - 3) = x² - 9”
Consecutive
Algebra
Definition
In a row, without skipping over any items.
Example
“14, 15, and 16 are consecutive integers; 19, 21, and 23 are consecutive odd integers”
Constant
Algebra
Definition
(1) The term of a polynomial that doesn't have a variable at all. (2) A parameter in a function that will always hold the same value, even for different points on the function.
Example
“In the polynomial 15x² - 19x + 7, the constant is 7. In y = 5x - 9, the constants are 5 and -9.”
Correlation
Statistics
Definition
A way to describe the trend in bivariate data. If the line of best fit has a positive slope, there is a positive correlation, and if the line of best fit has a negative slope, there is a negative correlation.
Example
“Strong positive correlation between study time and test scores”
Cosine
Trigonometry
Definition
In a right triangle, the ratio between the side adjacent to a given angle and the hypotenuse.
Example
“cos x = adjacent/hypotenuse”
Cylinder
Geometry
Definition
A 3-D geometric figure with two circular bases. It looks a lot like a soda can.
Example
“A soda can or pipe”
Decreasing
Functions
Definition
Getting smaller. A function is decreasing when, if you trace along the function from left to right, you are going in a downward direction.
Example
“A downward sloping line”
Degree
Algebra
Definition
(1) A way to describe a polynomial by giving the highest exponent. (2) A unit used to measure an angle.
Example
“15x⁷ - 12x⁴ + 3x - 1 is a 7th degree polynomial. A right angle has 90°.”
Deposit
Finance
Definition
The amount of money put into a bank account. This does not include any interest earned on that money.
Example
“Jack opens up a new bank account and makes an initial deposit of $100.”
Diameter
Geometry
Definition
The longest distance from one side of a circle to another. The diameter is twice the radius and will always go through the center of its circle.
Example
“The width of a circle”
Domain
Functions
Definition
All the values of x you can use in a function. Most functions have an infinite domain; the exceptions are rational functions, where you have to make sure the denominator will not be zero, and radical functions, where you have to make sure the value under the square root is ≥ 0.
Example
“The domain of f(x) = -7x² - 4 is infinite because you can plug in any x value at all and get an answer.”
Elements
Sets
Definition
The individual items in a set
Example
“The set {-7, 7} has two elements.”
Equation
Algebra
Definition
A mathematical statement that includes an equal sign.
Example
“2x + 3 = 7”
Equivalent
Algebra
Definition
Equal to, or the same as.
Example
“½ = 0.5 = 50%”
Exponential Decay
Functions
Definition
Something that is getting smaller at an ever decreasing-rate. This is represented by a curve that starts off with a steep drop, but eventually levels off.
Example
“Starting with a value such as 300 and cutting it in half over and over. The function f(x) = 300(0.5ˣ) models this situation.”
Exponential Growth
Functions
Definition
Something that is growing at an ever-increasing rate. This is represented by a curved line that starts off almost flat, but eventually gets very steep.
Example
“Starting with the number 5, and doubling it over and over. The function f(x) = 5(2ˣ) models this example.”
Expression
Algebra
Definition
A mathematical statement consisting of numbers, variables, and/or operations that does not have an equal sign or inequality. Expressions cannot be solved; they can only be simplified.
Example
“3x + 2y - 7”
FOIL
Algebra
Definition
An acronym that describes the process of multiplying two binomials. It stands for Firsts, Outers, Inners, Lasts.
Example
“(x² + 3)(2x - 5) = 2x³ - 5x² + 6x - 15”
Function
Functions
Definition
A mathematical description of the relationship between two variables. Typically, x is the input, and f(x) is the output. For a relation to be a function, there must be exactly one value of f(x) for each value of x.
Example
“f(x) = 2x - 1 is an example of a linear function”
Graph
Functions
Definition
A visual representation of the relationship between two variables. On the SAT, you will be analyzing graphs of functions and relations that are shown on the xy-plane.
Example
“A line, curve, or other shape plotted on coordinate axes”
Height
Geometry
Definition
The measurement from the bottom to the top, along a vertical line.
Example
“The height of a building”
Hypotenuse
Geometry
Definition
The side of a right triangle that is opposite the right angle. It will always be the longest side of the right triangle.
Example
“The longest side in a right triangle”
Imaginary Number
Algebra
Definition
The value that is equal to √-1 and is represented in math as i. In the real world, you can't take the square root of -1. When you're taking the SAT, make sure you know that i² = -1.
Example
“i, 2i, 3 + 4i”
Increasing
Functions
Definition
Getting larger. A function is increasing when, if you trace along the function from left to right, you are going in an upward direction.
Example
“An upward sloping line”
Inequality
Algebra
Definition
A statement describing the relationship between two expressions. There are 5 inequalities in math: <, ≤, >, ≥, and ≠.
Example
“x > 5, y ≤ 10”
Integers
Number Systems
Definition
All whole numbers and their opposites. Integers can be positive or negative, but cannot be fractions or have decimals.
Example
“5, -15, 92, and 0 are all integers. However, ½, 5.692, and √2 are not integers.”
Intercepts
Functions
Definition
The points at which the graph of a function crosses over one of the axes. The y-intercept will have coordinates (0,y) and the x-intercept, (x, 0).
Example
“The y-intercept of y = 2x + 3 is (0, 3)”
Interest
Finance
Definition
The money a bank will give you as a 'thank you' for saving your money at their institution. Simple interest is money given to you rather than deposited back into your account. Compounded interest is when the interest you earn is deposited into your account, and you start to gain interest on that interest.
Example
“5% annual interest on a $1000 savings account”
Isosceles Triangle
Geometry
Definition
A triangle with two equal sides. Isosceles triangles will have two congruent base angles and one different vertex angle. Isosceles right triangles will be 45-45-90 triangles.
Example
“A triangle with two sides of length 5 and one side of length 3”
Line
Geometry
Definition
A geometric figure that extends infinitely in two directions and does not change direction.
Example
“A straight line that goes on forever”
Line of Best Fit
Statistics
Definition
A line drawn on a scatterplot to show the general trend of the data. The slope of your line of best fit would tell you if there is a positive or negative correlation to the data.
Example
“A line that best represents the trend in scatterplot data”
Linear
Functions
Definition
A relationship that has a constant slope. Equations in the form y = mx + b are linear.
Example
“y = 2x + 3”
Margin of Error
Statistics
Definition
A way to describe the level of uncertainty when a statistic about a population is being estimated by a sample from that population. The margin of error can be easily converted to a confidence interval, and vice versa.
Example
“Amy polled 100 people and asked them how they would vote in next week's election. 52% of them said they would vote for her. So, she estimates she will get 52% of the vote with a margin of error of ±5%.”
Maximum
Functions
Definition
(1) The largest value in a set of data. (2) The y-value of the highest point in a function.
Example
“The maximum value in {1, 5, 3, 9, 2} is 9”
Mean
Statistics
Definition
A statistic calculated by adding up all the numbers in a set and dividing by how many values were in that set. The mean is also called the average and describes the center of the data.
Example
“The mean of {2, 4, 6, 8} is (2+4+6+8)/4 = 5”
Median
Statistics
Definition
A statistic arrived at by putting the data in ascending order and selecting the middle number. If there are an even number of data points, the median is calculated by adding the two numbers in the center and then dividing by two.
Example
“The median of {1, 3, 5, 7, 9} is 5. The median of {1, 3, 5, 7} is (3+5)/2 = 4”
Minimum
Functions
Definition
(1) The smallest value in a set of data. (2) The y-value of the lowest point in a function.
Example
“The minimum value in {1, 5, 3, 9, 2} is 1”
Model
Functions
Definition
A mathematical equation that describes how variables relate to each other in the real world.
Example
“The model H = 1.88L + 32.02 can be used by archeologists to estimate a person's total height (H) from the length of the femur (L), where H and L are both in inches.”
Outlier
Statistics
Definition
A number or numbers in a set that just don't seem to belong with all the other numbers because they are much larger or much smaller than the rest of the group.
Example
“In the set {5, 7, 52, 58, 59, 62, 71, 80}, 5 and 7 are outliers.”
Parabola
Functions
Definition
The 'U' shaped curve that results from graphing a quadratic function.
Example
“The graph of y = x²”
Parallel
Geometry
Definition
In geometry, two lines in the same plane that will never intersect. In coordinate geometry, two lines that have equal slopes. In a system of equations, two lines that have no solution.
Example
“Railroad tracks”
Percentage
Number Systems
Definition
The expression of a decimal or fraction as a number out of 100.
Example
“0.5 is the same thing as ½, which are both the same thing as 50%.”
Perpendicular
Geometry
Definition
In geometry, two lines in a plane that meet at a right angle. In coordinate geometry, two lines whose slopes are opposite reciprocals.
Example
“The corner of a square”
Pi (π)
Geometry
Definition
A number in math that represents the ratio between the circumference of a circle and its diameter. It is an irrational number, but we usually round it to 3.14 or use the fraction 22/7.
Example
“π ≈ 3.14159...”
Population
Statistics
Definition
All of the elements in a group.
Example
“The USA has a population of approximately 329 million people.”
Product
Algebra
Definition
The result of multiplication
Example
“The product of 5 and 6 is 30.”
Pyramid
Geometry
Definition
A 3-D geometric shape that has a polygonal base and comes to a point at the top. The sides are all triangles.
Example
“The Great Pyramid of Giza”
Pythagorean Theorem
Geometry
Definition
An equation relating the three sides of a right triangle. Specifically, it is a² + b² = c² where a and b are the legs and c is the hypotenuse.
Example
“In a 3-4-5 triangle: 3² + 4² = 5², so 9 + 16 = 25”
Pythagorean Triples
Geometry
Definition
Sets of three integers that satisfy the Pythagorean theorem. The triples you should know for the SAT are 3-4-5 and 5-12-13.
Example
“3-4-5, 5-12-13, 8-15-17”
Quotient
Algebra
Definition
The result of division
Example
“The quotient of 20 and 5 is 4. (Note that order is important. The quotient of 5 and 20 is ¼.)”
Radian
Trigonometry
Definition
A unit of measurement for angles. A right angle is π/2 radians, a straight angle is π radians, and a whole circle is 2π radians.
Example
“Imagine there is a circle painted on the ground that has a radius of 4 feet. If you were to start at one point on the circle and walk along the circumference for 4 feet, then you will have walked along one radian, or about 57.3°, of the circle.”
Radius
Geometry
Definition
The distance between the center of any circle and any point on that circle. The radius is half of the diameter.
Example
“The distance from the center of a circle to its edge”
Range
Functions
Definition
(1) A statistic calculated by subtracting the smallest value from the largest value. (2) All possible y-values for a given function.
Example
“The range of f(x) = x² + 7 is from 7 to positive infinity.”
Rate
Algebra
Definition
A way to describe the comparison of two separate measurements, such as in miles per hour, dollars per gallon, or pages per minute.
Example
“60 miles per hour, $3.50 per gallon”
Ratio
Algebra
Definition
A comparison of two numbers, usually written as a fraction or in the form a:b.
Example
“If there are 2 watermelons and 15 pumpkins in a field, then the ratio of watermelons to pumpkins is 2:15.”
Real Number
Number Systems
Definition
Any number that can be located on a number line. All positives, negatives, decimals, and zero are real numbers. The only numbers that aren't real are imaginary numbers.
Example
“5, -3, 0.5, √2, π”
Rectangle
Geometry
Definition
A 4 sided figure with 4 right angles. Find the perimeter by adding up the 4 sides, and find the area by multiplying length by width.
Example
“A door or window”
Regular
Geometry
Definition
A geometric shape where all the sides are equal, and all the angles are equal. A regular triangle is an equilateral triangle. A regular quadrilateral is a square.
Example
“A square, equilateral triangle, regular pentagon”
Remainder
Algebra
Definition
The number 'left over' when you divide two numbers.
Example
“When you divide 13 by 5 you get 2 with a remainder of 3. (5×2=10, plus 3 more to get to 13.)”
Right
Geometry
Definition
An angle of exactly 90°, or a shape that includes an angle of 90°.
Example
“The corner of a square”
Root
Algebra
Definition
(1) A number that when multiplied by itself a certain number of times results in the given value. (2) Another word for the zeros or x-intercepts of a polynomial function.
Example
“The square root of 100 is 10 and the 5th root of 32 is 2.”
Sample
Statistics
Definition
A subset of a population.
Example
“Makenzie wants to know how the kids in her school feel about wearing uniforms, so she talks to a sample of 20 students randomly selected from the student body.”
Sampling Method
Statistics
Definition
The process a researcher uses to collect data from a portion of a population. This could be accomplished by making observations, running an experiment, or conducting a survey.
Example
“Random sampling, stratified sampling, cluster sampling”
Satisfies
Algebra
Definition
Causes an equation to be true
Example
“The value of x that satisfies 3x + 9 = 12 is 1.”
Scatterplot
Statistics
Definition
A method of displaying bivariate data by graphing each pair of numbers as a point with an x and y coordinate.
Example
“If you gathered information on how much time your classmates spent studying for a math quiz and each one's grade on the quiz, you could then graph your data on an xy-plane.”
Sector
Geometry
Definition
A portion of the area of a circle. If the circle was a pizza, your slice would be a sector, and the crust on your slice would be an arc.
Example
“A pizza slice”
Similar Triangles
Geometry
Definition
Two triangles that are the same shape, but not necessarily the same size. Their angles will be equal, but their sides will be proportional.
Example
“Two triangles with the same angles but different sizes”
Sine
Trigonometry
Definition
In a right triangle, the ratio between the side opposite a given angle and the hypotenuse.
Example
“sin x = opposite/hypotenuse”
SOHCAHTOA
Trigonometry
Definition
A mnemonic to help you remember three important formulas in trigonometry. sin x = opposite/hypotenuse, cos x = adjacent/hypotenuse, and tan x = opposite/adjacent.
Example
“SOH: Sine = Opposite/Hypotenuse, CAH: Cosine = Adjacent/Hypotenuse, TOA: Tangent = Opposite/Adjacent”
Solution
Algebra
Definition
(1) The value of a variable that makes an equation true. (2) The point(s) at which the graphs of two or more functions cross.
Example
“The solution of 5x - 7 = -2 is x = 1.”
Solution Set
Algebra
Definition
All possible values of the variable
Example
“If |x| = 7, then x can equal 7 or -7, and the solution set is {-7, 7}.”
Special Right Triangles
Geometry
Definition
Triangles with angles of 30°-60°-90° or with angles of 45°-45°-90°. These triangles are special because if you are given the length of any one of the sides, you can figure out the other two sides.
Example
“A 30-60-90 triangle with sides in the ratio 1:√3:2”
Sphere
Geometry
Definition
The set of all points in 3-D space that are equidistant from a given point. That given point is the center of the sphere.
Example
“A basketball or globe”
Standard Deviation
Statistics
Definition
A statistic that describes how spread out the data is. A low standard deviation means the data are gathered close to the mean, while a high standard deviation means that there are data points pretty far to the left and the right of the center.
Example
“Data with values {1, 2, 3, 4, 5} has a lower standard deviation than {1, 1, 1, 5, 5, 5}”
Sum
Algebra
Definition
The result of adding two or more values.
Example
“The sum of 1 and 1 is 2.”
System of Equations
Algebra
Definition
Multiple equations for which there are multiple unknown variables. For instance, if x and y are both unknowns, you need to have two equations to solve for them.
Example
“2x + 3y = 7 and x - y = 1”
Table
Statistics
Definition
Data that is organized into rows and columns.
Example
“A spreadsheet or data chart”
Tangent
Trigonometry
Definition
(1) In a right triangle, the ratio between the side opposite a given angle and side adjacent to that angle. (2) A line that touches a circle but doesn't go inside the circle.
Example
“tan x = opposite/adjacent”
Trapezoid
Geometry
Definition
A quadrilateral with exactly one pair of parallel sides, called the bases. If one of the sides is perpendicular to the bases, it is a right trapezoid. If the two non-parallel sides are congruent, it is an isosceles trapezoid.
Example
“A shape like a table with one pair of parallel sides”
Triangle
Geometry
Definition
A 2-D shape with three sides and three angles. The three angles will always add up to 180°.
Example
“Any three-sided shape”
Undefined
Algebra
Definition
This is what we say when someone tries to divide by zero or tries to describe the slope of a vertical line.
Example
“The slope of a vertical line is undefined”
Union of Two Sets
Sets
Definition
The set of elements that are in either one of two given sets.
Example
“The union of {1, 2, 3} and {3, 4, 5} is {1, 2, 3, 4, 5}”
Values of a Variable
Algebra
Definition
Numbers that the variable is able to represent.
Example
“The values of x that satisfy x² = 9 are 3 and -3.”
Vertical Line Test
Functions
Definition
An easy way to tell if a graph is a function. If you can draw a vertical line that passes through the graph in more than one place, then it's not a function.
Example
“A circle fails the vertical line test because a vertical line can pass through it twice”
Volume
Geometry
Definition
A measurement of how much space is inside a 3-D figure. The units that describe volume will be cubic (in³, ft³, cm³) or volume specific (gallon, Liter).
Example
“The volume of a box is length × width × height”
Weight
Physics
Definition
An object's mass times the acceleration due to gravity. Common units for weight are pounds (lbs) and Newtons (N).
Example
“A person's weight on Earth vs. the Moon”
x-axis
Coordinate Geometry
Definition
The horizontal baseline in the coordinate xy-plane.
Example
“The horizontal line on a graph”
xy-plane
Coordinate Geometry
Definition
A two dimensional system in which the exact location of any point can be described by giving its distance from the baseline horizontal and vertical axes.
Example
“A coordinate plane with x and y axes”
y-axis
Coordinate Geometry
Definition
The vertical baseline in the coordinate xy-plane.
Example
“The vertical line on a graph”
Zeros
Functions
Definition
Another word for the roots or x-intercepts of a polynomial function. Find the zeros by setting the function equal to zero and solving.
Example
“The zeros of f(x) = x² - 4 are x = 2 and x = -2”

Master SAT Math next

Pair this glossary with problem practice and full-length tests.

Start practice tests More resources

Stay consistent with daily prep — track habits with Resolve, a self-improvement habit tracking app.

Filter glossary by category

Math terms glossary

Master SAT Math next