What is pl. An optical instrument consisting of two lenses set in a light frame, and worn to assist sight, to obviate some defect in the organs of vision, or to shield the eyes from bright light called?

spectacle — pl. An optical instrument consisting of two lenses set in a light frame, and worn to assist sight, to obviate some defect in the organs of vision, or to shield the eyes from bright light. (Webster's 1913.)

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