contact lens 
noun
A thin plastic lens placed directly on the surface of the eye to correct visual defects: [as modifier]: contact lens wearers...
- You would save a lot if you purchased your Halloween lenses from an online contact lens retailer instead.
- With this option, you wear a bifocal contact lens in your nondominant eye and a contact lens set for distance in your dominant eye.
- Note that the leaves flip by almost turning inside out - similar to the flipping of a contact lens, plastic lid or the reversal of a torn tennis ball.