Bar and bat mitzvah mean, literally, son and daughter of the commandment.. Bat mitzvah is Hebrew, while bar mitzvah, historically a much earlier ceremony, is Aramaic. The word bar is the Aramaic equivalent of the Hebrew ben (son of) .
In math, the mean is the average of a set of numbers. To determine the mean, add all numbers in a set and take this answer and divide it by how many numbers are in the set. Continue Reading.
noun. 1  Something having a position, quality, or condition midway between extremes; a medium. 2  Mathematics a. A number that typifies a set of numbers, such as a geometric mean or an arithmetic mean. 3  Logic The middle term in a syllogism. 4  means used with a sing. or pl.