What does the term "dewpoint" refer to?

The term "dewpoint" refers to the temperature at which air becomes saturated with moisture, meaning it cannot hold any additional water vapor. When the air temperature drops to this point, the water vapor present begins to condense into liquid form, resulting in dew, fog, or clouds. This concept is crucial in meteorology as it provides insight into humidity levels and potential weather conditions.

Understanding dewpoint is essential for a variety of applications, including aviation, agriculture, and HVAC systems, as it affects visibility, cloud formation, and comfort levels in indoor environments. The other choices do not accurately capture the meaning of dewpoint; for instance, the highest altitude and absolute humidity pertain to different atmospheric concepts, and the pressure point in an aircraft relates to mechanical engineering rather than meteorological terms.