contact lens

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A thin plastic or glass lens that is fitted over the cornea of the eye to correct various vision defects.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A thin lens, made of flexible or rigid plastic, that is placed directly on to the eye to correct vision, used as an alternative to spectacles, or, if coloured, to change one's eye color cosmetically.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication