What is "apodization"

n. (context mathematics English) Any of several techniques to modify the form of a mathematical function, or of a spectrum etc. by smoothing or removing irregularities.

Apodization is an optical filtering technique, and its literal translation is "removing the foot". It is the technical term for changing the shape of a mathematical function, an electrical signal, an optical transmission or a mechanical structure. In optics, it is primarily used to remove Airy disks caused by diffraction around an intensity peak, improving the focus.