n. a tendency to squint in which the eye, when covered, tends to turn outwards. The eye always straightens on removal of the cover. See also heterophoria.
n. a tendency to squint. Normally both the eyes work together and look at the same point simultaneously, but if one eye is covered it will move out of alignment with the object the other eye is still viewing. When the cover is removed the eye immediately returns to its normal position. Most people have a small degree of heterophoria in which the covered eye turns outwards, away from the nose (exophoria; compare esophoria). Heterophoria may produce eyestrain because of the unconscious effort required to keep the two eyes aligned. See also strabismus.... heterophoria
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