What is a high leverage point?

A high leverage point specifically refers to an observation in which the value of a predictor is considered to be extreme in the feature space. Thus, leverage points can be considered outliers in the context of the predictor space (X), whereas in regression analysis, outliers usually specifically refer to the scope of the target variable (Y). 

The red dot in the above chart represents a leverage point. Since the point follows the general trend of data, it is not necessarily an outlier