# StudyMaths.co.uk

## Glossary - Mathematical words you need to know

A collection of mathematical words and their meanings. It may be useful to print these off and use them as a revision aid. Make sure you understand them all before your exam!

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
Acute angleAn angle less than 90°.
AdjacentAdjacent sides are next to each other and are joined by a common vertex.
AlgebraAlgebra is the branch of mathematics where symbols or letters are used to represent numbers.
AngleAn angle is formed when two straight lines cross or meet each other at a point. The size of an angle is measured by the amount one line has been turned in relation to the other.
ApproximateAn approximate value is a value that is close to the actual value of a number.
ArcPart of a circumference of a circle.
AreaThe amount of space a shape takes up. E.g. the area of the lawn is 35 square metres.
AsymmetricalA shape which has no lines of symmetry.
AverageA value to best represent a set of data. There are three types of average - the mean, the median and the mode.
AxisAn axis is one of the lines used to locate a point in a coordinate system.
B
BearingA three digit angle measured from north in a clockwise direction.
BIDMASA way of remembering the order in which operations are carried out. It stands for Brackets - Indices - Division - Multiplication - Addition - Subtraction.
BisectTo divide an angle or shape exactly in half.
BracketsUsed to determine the order in which operations are carried out. For example, 3 + 4 x 2 = 11 but (3 + 4) x 2 = 14.
C
CalculateTo work out the value of something. This does not have to mean you need a calculator!
Centilitre (cl)A measure of volume. 100 centilitres = 1 litre (100 cl = 1 l). 1 centilitre = 10 millilitres (1 cl = 10 ml).
Centimetre (cm)A measure of distance. 1 centimetre = 10 millimetres. (1 cm = 10 mm). 100 centimetres = 1 metre. (100 cm = 1 m).
ChordA straight line drawn from one point on the edge of a circle to another.
CircumferenceThe perimeter of a circle.
CoefficientThe number in front of an algebraic symbol. For example the coefficient of 5x is 5.
CongruentIf you can place a shape exactly on top of another then they are said to be congruent. You may rotate, reflex or translate the shape.
ConstantA letter or symbol whose value always stays the same. The constant Π is a common example.
CreditTo add money to a bank account. For example, I had £500 credited to my bank account.
Cross sectionThe end section created when you slice a 3D shape along it's length.
Cube numberThe product when an integer is multiplied by itself twice. For example 5 cubed = 5 x 5 x 5 = 125.
CuboidA 3D shape with all sides made from rectangles.
Cumulative frequencyA running total of the frequencies, added up as you go along.
D
DayA time period of 24 hours. There are 7 days in a week.
DebitTo take out money from a bank account. For example, £400 was debited from my account.
DecagonA ten sided polygon.
DecimalNot a whole number or integer. For example, 3.6 or 0.235.
DecreaseTo make an amount smaller.
DenominatorThe bottom part of a fraction.
DiameterThe distance across a circle which passes through the centre.
DifferenceSubtract the smaller value from the larger value to find the difference between two numbers.
DistanceHow far away an object is. For example, it is a distance of 3 miles to the city centre.
DistributionHow data is shared or spread out.
E
EqualUsed to show two quantities have the same value.
EquationTwo expressions which have the same value, separated by an '=' sign. E.g. 3y = 9 + y
Equilateral triangleA triangle with all sides and angles the same size.
EstimateTo find an approximate answer to a more difficult problem. E.g. 31.2 x 5.94 is roughly equal to 30 x 6 = 180.
Even numberAny number which is a multiple of 2. Even numbers always end in 2, 4, 6, 8 or 0.
ExpandTo multiply out brackets in an expression. For example, 2(3x + 7) = 6x + 14.
ExpressionA collection of terms which can contain variables (letters) and numbers. E.g. 4pq - q + 7
F
FactorA number that divides another number exactly. E.g. 4 is a factor of 12.
FactoriseTo put an expression into brackets by taking out a common factor. For example, 20x + 15y = 5(4x + 3y).
FiguresAnother name for numbers. For example one thousand and fifty in figures is 1050.
FormulaAn equation used to describe a relationship between two or more variables.
FrequencyHow many times something happens. Another word for 'total'.
Frequency densityThe frequency divided by the class width.
G
GradientHow steep a line is. Found by dividing the distance up by the distance across.
Gram (g)A measure of mass. 1 gram = 1000 milligrams. (1 g = 1000 mg)
H
HCFStands for 'highest common factor'. It is the largest factor common to a set of numbers. E.g. The HCF of 16 and 24 is 8.
HeptagonA seven sided polygon.
HexagonA six sided polygon.
HistogramA diagram drawn with rectangles where the area is proportional to the frequency and the width is equal to the class interval.
HypotenuseThe longest side on a right angled triangle.
I
IncreaseTo make an amount larger.
IndicesAnother name for powers such as ² or ³.
IntegerA whole number.
Inter-quartile range (IQR)The difference between the upper and lower quartile.
IrrationalA decimal which is never ending. It must also not be a recurring decimal.
J
JustifyAnother word for 'explain'. Often crops up on your maths exam. E.g. 'Calculate the mean and range for each player. Who is the better player Justify your answer.'
K
Kilogram (Kg)A measure of mass. 1 kilogram = 1000 grams. (1 kg = 1000 g)
Kilometre (Km)A measure of distance. 1 kilometre = 1000 metres. (1 km = 1000 m)
L
LCMStands for 'lowest common multiple'. It is the smallest multiple common to a set of numbers. E.g. The LCM of 3 and 4 is 12.
Litre (l)A measure of volume. 1 litre = 100 centilitres (1 l = 100 cl). 1 litre = 1000 millilitres (1l = 1000 ml).
LociThe plural of locus.
LocusA collection of points which are the same distance from another point or line.
Lower rangeThe smallest value in a set of data.
M
MeanA type of average found by adding up a list of numbers and dividing by how many numbers are in the list.
MedianThe middle value when a list of numbers is put in order from smallest to largest. A type of average.
Metre (m)A measure of distance. 1 metre = 100 centimetres. (1 m = 1000 cm).
Millilitre (ml)A measure of volume. 10 millimetres = 1 centilitre (10 ml = 1 cl). 1000 millilitres = 1 litre (1000 ml = 1 l).
Millimetre (mm)A measure of distance. 10 millimetres = 1 centimetre. (10 mm = 1 cm).
ModalAnother term for mode
ModeThe most common value in a list of numbers. If two values are tied then there is two modes. If more than two values are tied then there is no mode. A type ofaverage.
MonthA time period of either 28, 29, 30 or 31 days. There are 12 months in a year.
MultipleA number which is part of another number's times table. E.g. 35 is a multiple of 5.
N
Natural numberA positive integer
NegativeA value less than zero
NonagonA nine sided polygon.
NumeratorThe top part of a fraction.
O
Obtuse angleAn angle between 90°�and 180°.
OctagonAn eight sided polygon.
Odd numberA number that is not a multiple of 2. Odd numbers always end in 1, 3, 5, 7 or 9.
OperationAn action which when applied to one or more values gives an output value. The four most common operations are addition. subtraction, multiplication and division.
P
ParallelTwo or more lines which are always the same distance apart.
ParallelogramA quadrilateral with two pairs of parallel sides.
PentagonA five sided polygon.
PerimeterThe distance around a shape.
PerpendicularTwo or more lines which meet at right angles.
Pi (Π)An irrational constant used when calculating the area and circumference of circles. It is approximately equal to 3.14.
PolygonA shape made from straight lines.
Positive numberA number greater than zero.
PrimeA number which has exactly two factors. The number one and itself.
PrismA 3D shape with the same cross section all along its length.
ProbabilityA measure of how likely an event is to occur.
ProductThe answer when two values are multiplied together.
Q
Quadratic equationAn equation where the highest power is two. For example x² + 4x + 6 = 0 is a quadratic equation.
R
RadiusThe distance from the centre of a circle to its circumference. The plural of radius is radii.
Random samplingA method of choosing people at random for a survey.
RangeThe largest number take away the smallest value in a set of data.
RationalA decimal number which ends or is recurring.
ReciprocalThe reciprocal of any number is 1 divided by the number. E.g. the reciprocal of 3 is 1/3., the reciprocal of 3/4 is 4/3.
RecurringA decimal which never ends but repeats all or parts of the sequence of numbers after the decimal point. E.g 0.333333 or 0.141414.
Reflex angleAn angle greater than 180°.
RegularA shape with all sides and angles the same size.
RemainderThe amount left over when a number cannot be divided exactly. For example, 21 divided by 4 is 5 remainder 1.
Right angleAn angle of 90°.
RotationTo turn a shape using an angle, direction and centre of rotation.
RoundTo reduce the amount of significant figures or decimal places a number has. For example £178 rounded to the nearest £10 is £180.
S
Scale factorHow many times larger or smaller an enlarged shape will be.
SegmentAn area of a circle enclosed by a chord.
SequenceA list of numbers which follows a pattern. For example 6, 11, 16, 21, ...
SimplifyTo write a sum, expression or ratio in its lowest terms. For example 4:10:6 can be simplified to 2:5:3.
SolidA 3D shape.
SolveTo find the missing value in an equation.
SpeedHow fast an object is moving. Average speed = Total distance divided by time taken.
Square numberThe product when an integer is multiplied by itself. For example, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100.
Surface areaTo total area of all sides on a 3D shape.
SymmetricalA shape which has at least one line of symmetry.
T
TallyA system of counting where every group of four vertical lines is followed by a horizontal line to easily count in steps of five.
TangentA straight line that just touches a point on a curve. A tangent to a circle is perpendicular to the radius which meets the tangent.
TermA number, variable or combination of both which forms part of an expression.
TransformationThe collective name for reflections, rotations, translations and enlargements.
TranslationTo move a shape from one position to another by sliding in the x-axis followed by the y-axis.
TrapeziumA quadrilateral with one pair of parallel sides.
Tree diagramA method of solving probability questions by listing all the outcomes of an event. Probabilities are calculated by multiplying down the branches.
TriangleA three sided polygon.
Triangular numberA sequence of numbers generated by adding one more than was added to find the previous term. For example, 1, 3, 6, 10, 15, 21, ...
U
UnitsA quantity used to describe a measurement. Examples are kilograms, metres and centilitres.
Upper rangeThe largest value in a set of data.
V
ValueA numerical amount or quantity.
VariableA letter which we don't know the value of.
VolumeThe amount an object can hold. E.g. a bottle of cola has a volume of 2 litres.
W
WeekA time period of 7 days.
WideUsed to describe the width of something
WidthThe distance from side to side. E.g. 'The swimming pool is 10 metres wide.'
X
X-AxisThe horizontal axis on a graph. The line going across the page.
Y
Y-AxisThe vertical axis on a graph. The line going from top to bottom.
Y-InterceptThe value of the y-coordinate when a graph crosses the y-axis.
YearA time period of 12 months or 365 days. (366 in a leap year.)
Z
Z-AxisRepresents the depth of an object when working with 3D coordinates.