Arithmetic mean

The full term for what non-mathematicians intuitively call the average and which is generally shortened simply to the mean. It is calculated by taking the sum of a series of values and dividing that number by the number of values. So if 12 values add up to 96, the average is eight. It should not be confused with the geometric mean, under which heading there is a fuller discussion of the circumstances in which it is more appropriate to use one or the other.