Name from west to east the four Great Lakes shared by Canada and the US Lake Superior, Lake Huron, Lake Erie, Lake Ontario Name the Great Lake that lies entirely in the boundaries of the US.
Definition of ophthalmology for English Language Learners. medical : the study of the structure, functions, and diseases of the eye.
visual acuity. noun, Ophthalmology. 1. acuteness of the vision as determined by a comparison with the normal ability to define certain letters at a given distance, usually 20 feet (6 meters). Abbreviation: V. Origin of visual acuity.