Year 7 vocabulary glossary

integer

An integer is a whole number, which can be positive, negative or zero, such as -3, 0 or 7.

decimal

A decimal is a number written using a decimal point to show parts smaller than one, such as 3.5.

fraction

A fraction shows part of a whole, written as one number over another, such as 3/4.

numerator

The numerator is the top number in a fraction, showing how many parts you have.

denominator

The denominator is the bottom number in a fraction, showing how many equal parts the whole is split into.

mixed number

A mixed number combines a whole number and a fraction, such as 2 1/2.

improper fraction

An improper fraction has a numerator bigger than its denominator, such as 7/2.

equivalent fraction

Equivalent fractions look different but represent the same amount, such as 1/2 and 2/4.

negative number

A negative number is less than zero, written with a minus sign, such as -5.

directed number

A directed number is a positive or negative number used to show a value's direction from zero, such as -4 or +6.

sum

The sum is the answer you get when you add numbers together.

difference

The difference is the answer you get when you subtract one number from another.

product

The product is the answer you get when you multiply numbers together.

quotient

The quotient is the result of a division, such as 5 in 20 ÷ 4 = 5, sometimes written with a remainder alongside it.

factor

A factor is a whole number that divides exactly into another number, with no remainder.

multiple

A multiple is a number found by multiplying a given number by a whole number, such as 12 being a multiple of 4.

prime number

A prime number has exactly two factors: 1 and itself, such as 2, 3, 5 or 7.

composite number

A composite number has more than two factors, such as 8, which is divisible by 1, 2, 4 and 8.

prime factor

A prime factor is a factor of a number that is also a prime number.

prime factorisation

Prime factorisation means writing a number as a product of its prime factors, such as 12 = 2 x 2 x 3.

factor pair

A factor pair is two numbers that multiply together to give a particular number, such as 3 and 4 for 12.

highest common factor (HCF)

The highest common factor is the largest number that divides exactly into two or more numbers.

lowest common multiple (LCM)

The lowest common multiple is the smallest number that is a multiple of two or more numbers.

reciprocal

The reciprocal of a number is 1 divided by that number, so the reciprocal of 5 is 1/5.

inverse operation

An inverse operation undoes another operation, such as subtraction undoing addition.

place value

Place value is the value of a digit depending on its position in a number, such as the 4 in 4,000 being worth four thousand.

rounding

Rounding means changing a number to a simpler, close value, such as rounding 47 to the nearest 10 to get 50.

estimate

An estimate is a sensible approximate answer, often found by rounding before calculating.

order of operations

The order of operations is the agreed sequence for working out a calculation with several steps: brackets, indices, multiplication/division, then addition/subtraction.

index (power)

An index, or power, shows how many times a number is multiplied by itself, such as the 3 in 2³.

square number

A square number is the result of multiplying a whole number by itself, such as 25, which is 5 x 5.

square root

The square root of a number is the value that multiplies by itself to give that number, so the square root of 25 is 5.

cube number

A cube number is the result of multiplying a whole number by itself twice more, such as 27, which is 3 x 3 x 3.

expression

An expression is a mathematical phrase made of numbers, letters and operations, such as 3x + 2, with no equals sign.

term (algebra)

A term is a single part of an expression, such as 3x or 7 in the expression 3x + 7.

like terms

Like terms contain exactly the same letter part, such as 3x and 5x, and can be added or subtracted together.

coefficient

The coefficient is the number in front of a letter in a term, such as the 3 in 3x.

variable

A variable is a letter used to represent a number that can change, such as x or y.

constant

A constant is a fixed number in an expression that does not change, such as the 5 in 2x + 5.

simplify

To simplify an expression means to write it in a shorter form by collecting like terms.

substitute

To substitute means to replace a letter in an expression or formula with a given number.

formula

A formula is a rule written using letters and symbols that shows the relationship between quantities, such as A = l x w.

subject of a formula

The subject of a formula is the letter on its own on one side of the equals sign, such as A in A = l x w.

sequence

A sequence is a list of numbers or shapes that follow a rule, one after another.

term-to-term rule

A term-to-term rule describes how to get from one term in a sequence to the next.

position-to-term rule

A position-to-term rule (or nth term rule) works out any term in a sequence directly from its position.

nth term

The nth term is an expression that gives the value of any term in a sequence when you substitute in its position number.

linear sequence

A linear sequence increases or decreases by the same amount each time, such as 2, 5, 8, 11.

common difference

The common difference is the fixed amount added or subtracted between consecutive terms in a linear sequence.

ascending

Ascending means arranged in order from smallest to largest.

descending

Descending means arranged in order from largest to smallest.

equation

An equation states that two expressions are equal, using an equals sign, such as 2x + 1 = 7.

unknown

An unknown is a letter in an equation whose value you need to find.

solve

To solve an equation means to find the value of the unknown that makes it true.

balance method

The balance method solves equations by doing the same operation to both sides, keeping the equation balanced like scales.

function

A function is a rule that takes an input number and produces exactly one output number.

input and output

The input is the number you put into a function or rule, and the output is the result it produces.

algebraic expression

An algebraic expression is a combination of letters, numbers and operations with no equals sign, such as 4x - 3.

evaluate

To evaluate an expression means to work out its value, usually by substituting in numbers.

angle

An angle is a measure, in degrees, of the amount of turn between two lines that meet at a point.

acute angle

An acute angle is an angle that measures less than 90 degrees.

obtuse angle

An obtuse angle is an angle that measures more than 90 but less than 180 degrees.

right angle

A right angle measures exactly 90 degrees, often shown by a small square in a diagram.

reflex angle

A reflex angle is an angle that measures more than 180 but less than 360 degrees.

protractor

A protractor is a tool used to measure or draw angles accurately, in degrees.

degree

A degree is the unit used to measure the size of an angle, with a full turn equal to 360 degrees.

perimeter

The perimeter is the total distance around the outside edge of a shape.

area

Area is the amount of space inside a 2-D shape, measured in square units such as cm².

rectangle

A rectangle is a quadrilateral with four right angles and opposite sides of equal length.

parallelogram

A parallelogram is a quadrilateral with two pairs of parallel, equal-length sides.

base (of a shape)

The base is the side of a shape, often at the bottom, that a shape's perpendicular height is measured from.

perpendicular height

The perpendicular height is the height measured at a right angle to the base, used to calculate area.

2-D shape

A 2-D shape is a flat shape with only two dimensions: length and width.

polygon

A polygon is a closed 2-D shape made of straight sides, such as a triangle, quadrilateral or pentagon.

regular polygon

A regular polygon has all sides equal in length and all angles equal in size.

irregular polygon

An irregular polygon has sides and/or angles that are not all equal.

quadrilateral

A quadrilateral is a 2-D shape with four straight sides, such as a square, rectangle or trapezium.

vertex (vertices)

A vertex is a corner point where two or more edges of a shape meet; vertices is the plural.

line of symmetry

A line of symmetry divides a shape into two mirror-image halves.

rotational symmetry

A shape has rotational symmetry if it looks the same after being rotated part-way around its centre.

order of rotational symmetry

The order of rotational symmetry is the number of times a shape matches its original position during one full turn.

congruent

Congruent shapes are exactly the same size and shape as each other.

net

A net is a 2-D shape that can be folded up to make a 3-D shape.

construction (maths)

A construction is an accurate drawing made using only a ruler and compasses, following exact geometric rules.

data

Data is information, often in the form of numbers, that has been collected for analysis.

discrete data

Discrete data can only take exact, separate values, such as the number of pets a person owns.

continuous data

Continuous data can take any value within a range, such as height or time.

frequency

Frequency is the number of times a particular value or event occurs in a set of data.

frequency table

A frequency table lists values or categories alongside how often each one occurs.

tally chart

A tally chart uses tally marks to record data as it is collected, grouped in fives for easy counting.

bar chart

A bar chart displays data using rectangular bars, with the height or length showing the frequency.

pictogram

A pictogram uses repeated symbols or pictures to represent data, with each symbol standing for a set amount.

average

An average is a single value used to represent the middle or typical value of a data set, such as the mean, median or mode.

mode

The mode is the value that occurs most often in a data set.

median

The median is the middle value in a data set when the values are arranged in order.

mean

The mean is found by adding all the values in a data set and dividing by how many values there are.

range

The range is the difference between the largest and smallest values in a data set.

outlier

An outlier is a value in a data set that is much higher or lower than the rest of the data.

stem-and-leaf diagram

A stem-and-leaf diagram organises numerical data by splitting each value into a 'stem' and a 'leaf' to show its shape and order.

key (data diagram)

A key explains what the symbols or values in a chart or diagram represent.

survey

A survey is a method of collecting data by asking people questions.

questionnaire

A questionnaire is a set of written questions used to collect data from people.

sample

A sample is a smaller group chosen from a larger population, used to represent that population in data collection.

population (statistics)

In statistics, the population is the entire group being studied, from which a sample may be taken.

bias

Bias is anything in the way data is collected that makes the results unfair or not representative.

primary data

Primary data is data you collect yourself, first-hand, for a specific purpose.

secondary data

Secondary data is data that has already been collected by someone else.

grouped data

Grouped data is data organised into class intervals, such as 0-10, 11-20, rather than listed individually.

class interval

A class interval is a range of values used to group data, such as 10-19 or 20-29.