This glossary includes essential math definitions for high school students, including terms from algebra, geometry, trigonometry, calculus, and statistics. Use it as a study tool, reference guide, or for test preparation.
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Arithmetic & Number Systems
- Absolute value
- Distance of a number from zero on the number line.
- Addend
- Numbers being added.
- Integer
- A whole number (positive, negative, or zero).
- Rational number
- Can be written as a ratio of two integers.
- Irrational number
- Cannot be expressed as a simple fraction (e.g., π, √2).
- Real number
- Includes all rational and irrational numbers.
- Prime / Composite
- Prime has only 2 divisors; composite has more than 2.
- Factor / Multiple
- Factor divides a number; multiple is a product of a number and an integer.
- Exponent / Power
- Indicates repeated multiplication.
- Square root / Cube root
- Inverses of squaring or cubing.
- Scientific notation
- Expressing numbers in the form a × 10ⁿ.
Arithmetic Operations
- Addition / Subtraction
- Combining or removing values.
- Multiplication / Division
- Repeated addition / partitioning.
- Order of Operations (PEMDAS)
- Parentheses, Exponents, Multiply/Divide, Add/Subtract.
Algebra
- Variable / Constant / Coefficient
- Symbols for unknowns, fixed values, and multipliers.
- Expression / Polynomial / Term
- Mathematical phrases with numbers and variables.
- Equation / Inequality
- Equality or relational statements.
- Function Types
- Linear, quadratic, exponential, logarithmic.
- Slope / Intercept
- Rate of change / point where a graph crosses an axis.
- Domain / Range
- All possible inputs and outputs of a function.
- Factorization / Quadratic Formula
- Methods for solving quadratic equations.
- Systems of Equations
- Two or more equations with multiple variables.
Geometry
- Point / Line / Segment / Ray
- Basic building blocks of geometry.
- Angle Types
- Acute, right, obtuse, complementary, supplementary.
- Triangle / Polygon / Quadrilateral
- Closed shapes with 3+ sides.
- Congruence / Similarity
- Same size and shape / same shape only.
- Pythagorean Theorem
- a² + b² = c² for right triangles.
- Circle Elements
- Radius, diameter, chord, arc, tangent.
- Area / Perimeter / Volume
- Measures of 2D/3D space.
- Transformation
- Translation, rotation, reflection, dilation.
- Coordinate Geometry
- Using coordinates to solve geometric problems.
Statistics & Probability
- Mean / Median / Mode
- Measures of central tendency.
- Range / IQR / Standard Deviation
- Measures of variability.
- Graphs
- Histogram, box plot, scatter plot, bar graph.
- Probability
- Chance of a particular event happening.
- Permutation / Combination
- Arrangements with and without order.
- Correlation vs. Causation
- Association vs. cause-effect relationship.
Trigonometry
- Trigonometric Ratios
- Sine, cosine, tangent.
- Unit Circle / Radians
- Angle measures beyond degrees.
- Law of Sines / Cosines
- Solving non-right triangles.
Calculus (Intro)
- Limit / Continuity
- Behavior of a function near a point.
- Derivative
- Instantaneous rate of change.
- Integral
- Total area under a curve.