What is the term for the total amount of water vapor present in a column of air?

The term for the total amount of water vapor present in a column of air is referred to as precipitable water. This measurement indicates the depth of water that would result if all of the water vapor in a column of air were to be condensed and collected as liquid water. It is a critical factor in meteorology, as it helps in understanding weather patterns, precipitation potential, and the overall moisture content in the atmosphere.

While humidity generally describes the concentration of water vapor in the air at a specific temperature and pressure, it does not specifically quantify the total amount over a vertical column. Vapor pressure refers to the pressure exerted by water vapor in the air but does not indicate the total water vapor content. Atmospheric moisture content is a broader term that could encompass various measurements related to moisture but lacks the precise definition that precipitable water provides.