British Dictionary definitions for weighted average
weighted average
noun
1.
an average calculated by taking into account not only the frequencies of the values of a variable but also some other factor such as their variance. The weighted average of observed data is the result of dividing the sum of the products of each observed value, the number of times it occurs, and this other factor by the total number of observations
for a series of recorded observations, the sum of the products of the frequency of certain values and the value of the observation, divided by the total number of observations