The outlier is a number in a set of numbers that stands apart from those other numbers. In other words, if you had 4.5, 4.6, 4.67, and 73, 73 would be the outlier because it's far greater than those other numbers. Even if you had, for example, 4.5, 6, 7.1, and 73, 73 would still be the outlier. This works for negative numbers as well, or numbers that are far smaller than most of the others.
