The normal annual value of discharge can be described using several synonyms that accurately convey its meaning. One such synonym is the average annual flow, which refers to the volume of water that passes through a given point in a watercourse over one year. Another related phrase is the mean annual discharge, which refers to the average quantity of water that flows past a point in a river during a calendar year. Other similar terms include the typical annual discharge or the regular annual flow, both describing the expected amount of water that is expected to flow through a particular watercourse on an annual basis.