GCSE Maths Keywords and Definitions

Understanding GCSE Maths vocabulary is extremely important. Many students lose marks because they misunderstand the meaning of words in questions.

Good maths vocabulary helps students:

  • understand exam questions correctly
  • choose the right method
  • avoid common mistakes
  • communicate mathematical reasoning clearly

Algebra Keywords

Expression

A mathematical statement containing numbers, variables and operations.

Equation

A mathematical statement showing two expressions are equal.

Factorise

Writing an expression as a product of brackets or factors.

Topic page: Factorising

Expand

Multiplying brackets to remove them.

Topic page: Expanding Brackets

Substitute

Replacing variables with numbers or expressions.

Sequence

A list of numbers following a pattern or rule.

Topic page: Sequences

Number Keywords

Integer

A whole number, including negative numbers.

Prime Number

A number with exactly two factors: 1 and itself.

Multiple

A result found by multiplying a number.

Factor

A number that divides exactly into another number.

Reciprocal

The multiplicative inverse of a number.

Standard Form

Writing numbers in the form a × 10ⁿ.

Topic page: Standard Form

Geometry Keywords

Perimeter

The total distance around a shape.

Area

The amount of space inside a shape.

Topic page: Area and Perimeter

Hypotenuse

The longest side in a right-angled triangle.

Topic page: Pythagoras

Transformation

A movement or change of a shape.

Topic page: Transformations

Bearing

A direction measured clockwise from north.

Topic page: Bearings

Probability Keywords

Outcome

A possible result from an event.

Event

A situation or result being considered in probability.

Independent Events

Events where one outcome does not affect another.

Conditional Probability

Probability calculated based on another event already happening.

Topic page: Tree Diagrams

Statistics Keywords

Mean

The average found by dividing the total by the number of values.

Median

The middle value in an ordered list.

Mode

The most frequent value.

Range

The difference between the largest and smallest values.

Topic page: Mean Median Mode and Range

Histogram

A graph showing grouped continuous data using frequency density.

Topic page: Histograms

Important GCSE Exam Command Words

Calculate

Work out a numerical answer.

Solve

Find the value of an unknown variable.

Estimate

Find an approximate answer.

Show that

Demonstrate that a statement is true using clear mathematical working.

Explain

Give reasoning using mathematical evidence.

Exam tip:

Understanding the command words in GCSE Maths questions is often just as important as knowing the maths itself.

Useful GCSE Maths Revision Guides

Video explanation

A short Worthing Maths Tutor video explanation for GCSE Maths keywords and definitions can be embedded here later to improve student engagement and time on page.

Related GCSE Maths Pages

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