angular size

size, angular 

The size of an object measured in terms of the angle it subtends. The point of reference for the eye can be either the nodal point or the centre of the entrance pupil. See extended object; apparent size.
apparent s. 1. The size of an object represented by the angular size. 2. The perceived size of an object as distinguished from the actual size (Fig. S8).
s. constancy See size constancy.
s. lens See aniseikonic lens." >Fig. S8 Objects of different size seen in the same direction and with the same angular size stimulate the same retinal points and thus have the same apparent size