# Maths Vocab

This is a list of some maths terms with their definition and an example.  (More will be added soon)

Term Definition Example

Acute Angle

​An angle that measures less than 90o. ​Area

​The amount of space taken up by a 2D shape or surface.  Area is measured in square units for example cm2 or m2. ​Array

​A pictorial representation (rows or dots) to help children to understand multiplication and division. BIDMAS or BODMAS

​The order to complete mathematical calculations. ​Circumference

​The measurement all the way around the outside edge of a circle. ​Coordinates

​Numbers that give you a position on a grid marked by how far along they are on the x axis and how far up or down they are on the y axis.  Always write the x axis value first. ​Denominator

​The bottom number of a fraction that tells you how many parts a shape or amount has been divided equally into. Diameter

​The length of a straight line through the centre of a circle from one point on the circumference to another point. Divisor

​The number you are dividing by. Equilateral Triangle

A triangle where all sides are the same length and all angles are the same size. Exchanging

​Converting from one place value to another - a term used instead of "carrying" in addition and "borrowing" in subtraction. Factor

​A whole number which will divide exactly into another number. Highest Common Factor (HCF)

​The highest number that two or more whole numbers is divisible by.  It could be easier if you listed all the factors of each number. ​Index (Plural: Indices)

​Also know as "power", the index shows how many times the number is used in a multiplication. Isosceles Triangle

​Triangles that have 2 sides of equal length and 2 angles of equal size. ​Lowest Common Multiple (LCM)

​The lowest number that is a multiple of two or more numbers. ​Mean

​An average measure that is calculated by adding all the values in a data set together and dividing it by the number of values there are. ​Median ​An average measure that shows the middle value when a group of numbers is arranged in order of size. Mode

​An average measure that shows the value which appears most frequently in a set of data. Multiple

​A number that can be divided by a whole number without remainders. ​Number Bonds ​Numerator

​The number on the top of a fraction that tells you how many parts you have. Obtuse Angle ​An angle that measures more than 90o but less than 180o. ​Partitioning

​Expanding or breaking down a number into the individual values of each digit - this helps with understanding place value. ​Perimeter

​The distance measured around the outside of a 2D shape. Place Value

​The value of a digit within a number. Prime Number ​Numbers that only have two factors which are 1 and the number itself. ​The measurement of a straight line from the centre of a circle to any point on the circumference of a circle. ​Range

​An average measure that shows the difference between the highest and the lowest value in a data set. Ratio

​A comparison between the amounts of different things. ​Reflex Angle

​An angle that measures more than 180o but less than 360o. Right Angle

An angle that measures exactly 90o. Scalene Triangle ​A triangle where all the sides are of different lengths and all the angles are different values but one of the angles measures more than 90o. Square Number ​The value when a number is multiplied by itself. ​x axis

​The horizontal axis on a graph or grid.

Remember: "X is a-cross". ​y axis

​The vertical axis on a graph or grid. 