amblyopia (n.)
1706, "weakening of the eyesight without any apparent defect in the eyes," medical Latin, from Greek amblyopia "dim-sightedness," noun of action from amblys "dulled, blunt" (from a suffixed form of PIE root *mel- (1) "soft") + ōps "eye" (from PIE root *okw- "to see") + abstract noun ending -ia. Related: Amblyopic.