The pictorial graphical representation of the shape of a wave obtained by plotting the values of the periodic quantity against the time.
See Alexandrite Tsarstone collectors guide, Definition of Wave form of light, http://w.alexandrite.com/viewpage.html?id=GG-082-00002 (The pictorial graphical representation of the shape of a wave obtained by plotting the values of the periodic quantity against the time.) (as of Apr. 06, 2026, 18:43 GMT).