An airy equation is a second-order differential equation that describes the behavior of a certain mathematical function known as the Airy function. This equation is commonly used in physics and engineering to model wave phenomena, such as the propagation of light and sound. Synonyms for the term "airy equation" include "Airy differential equation", "Airy wave equation", and "Airy function equation". Some other related terms that are often used in conjunction with the airy equation are "Airy disc", "Airy pattern", and "Airy function zeros". These concepts are all linked to the mathematical properties and applications of the Airy function, and are widely studied in various fields of science and engineering.