(n.) An optical instrument for giving to pictures the appearance of solid forms, as seen in nature. It combines in one, through a bending of the rays of light, two pictures, taken for the purpose from points of view a little way apart. It is furnished with two eyeglasses, and by refraction or reflection the pictures are superimposed, so as to appear as one to the observer.
STEREOSCOPE
Meaning of STEREOSCOPE in English
Webster's English dictionary. Английский словарь Webster. 2012