Word Study
horopter
CIDE DICTIONARY
horopter, n. [Gr. boundary + one who looks.].
The line or surface in which are situated all the points which are seen single while the point of sight, or the adjustment of the eyes, remains unchanged. [1913 Webster]
"The sum of all the points which are seen single, while the point of sight remains unchanged, is called the horopter." [1913 Webster]
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