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.
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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.
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.
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.
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.
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.
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.
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