noun
: the small apparently circular disk of a star as seen in a telescope that limits the resolving power of the telescope and varies inversely with the diameter of the objective — called also diffraction disk
noun
: the small apparently circular disk of a star as seen in a telescope that limits the resolving power of the telescope and varies inversely with the diameter of the objective — called also diffraction disk
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012