lens
lens lenses
1 A lens is a thin curved piece of glass or plastic used in things such as cameras, telescopes, and pairs of glasses. You look through a lens in order to make things look larger, smaller, or clearer.
...a camera lens...
I packed your sunglasses with the green lenses.
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2 In your eye, the lens is the part behind the pupil that focuses light and helps you to see clearly.
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