Vocabulary.com Dictionary - Meanings, Definitions, Quizzes, and Word Games | Vocabulary.com SKIP TO CONTENT Dictionary Vocabulary Lists VocabTrainer™ Look up a word, learn it forever. Word Of The Day refractor A refractor is a kind of lens that bends light to form a focused image. A telescope that uses this type of lens to bring distant objects into view is also known as a refractor. The word refractor comes from refract, "to break or bend the natural course." In the case of a telescope, it's light that's being refracted, or bent, as it passes through a lens. A second lens magnifies the image, making it possible to see distant stars and planets. Today, most large telescopes used by astronomers to see very distant objects are reflecting telescopes that use mirrors rather than refractors. EXPLORE WORD OF THE DAY Want to expand your vocabulary? Get Word of the Day delivered straight to your inbox! Subscribe to our word of the day subscribed Editor's Choice What's your vocabulary proficiency score? Test your vocabulary proficiency level with our award-winning program and see how you rank against millions of English language learners worldwide. Get your score now Sign up now (it’s free!) Whether you’re a teacher or a learner, Vocabulary.com can put you or your class on the path to systematic vocabulary improvement. Get started Commonly Confused Words See all > A comprehensive guide to correct word choice scrimp / skimp These words are two sides of the same coin: ways to get more or to make something go further. One side is about saving; the other is about spending less. read more > prescribe / proscribe Warning! These similar sounding words have very different meanings. To prescribe is to recommend and to proscribe is to forbid. One little letter makes a big difference. read more > amoral / immoral Both have to do with right and wrong, but amoral means having no sense of either, like a fish, but the evil immoral describes someone who knows the difference, doesn't care, and says "mwah ha ha" while twirling a mustache. read more > correlation / corollary A correlation is exactly what it sounds like: a co-relation, or relationship — like the correlation between early birds waking up and the sun rising. But corollary is more like a consequence, like the corollary of the rooster crowing because you smacked it in the beak. Both words love the math lab but can hang with the rest of us, too. read more > conscious / conscience Both words have to do with the mind, but it's more important to be conscious, or awake, than conscience, or aware of right and wrong. Remain conscious while listening to your friend's moral dilemma so you can use your conscience to give good advice. read more > wave / waive To wave is to move to and fro, like when you wave your hand. Hello there! To waive, with a sneaky "i," is to give up your right to do something. read more > Finally, a dictionary with a soul Our definitions were written by humans, for humans. Each word has a friendly explanation that makes it easy to remember. Real world examples Discover thousands of example sentences from current newspapers, magazines, and literature. World’s smartest, fastest dictionary Find the word you’re looking for faster than any other online dictionary. That’s less time searching, more time learning. 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