intraocular lens: an artificial lens that is implanted into the eye of someone to replace a damaged natural lens or someone who has had a cataract removed
lens: a transparent optical device used to converge or diverge transmitted light and to form images
linguistic performance: (linguistics) a speaker's actual use of language in real situations; what the speaker actually says, including grammatical errors and other non-linguistic features such as hesitations and other disfluencies (contrasted with linguistic competence)