concave means “hollow out or round in” and is easy to remember because these surfaces “hole” in. The opposite is rough means “curved or rounded outward.” Both words have existed for centuries but are often confused.
The advice in the mirror may be closer than it appears.
Merriam-Webster is a very serious company (although we like to be seen as a dictionary concernuse the 4th sense of mind as a noun), and so when we’re asked to help people distinguish between two easily confused words, we don’t indulge in silly mnemonics.
ARE NOT! For us, not bland memory aids, but “remember that .” advice X start with a Y.” Instead, we give you serious tools, such as the etymology of each word, and thus allow you to distinguish between them like a scholar.
Remember ‘Concave’ vs ‘Convex’
So if you need to tell the difference between concave And rough just remember that rough derived from the Latin word exophthalmisis, can mean “convex” or “concave” or … wait a minute. Please ignore our previous advice.
If you need to distinguish between these two words, just remember that concave since cave in it (because it’s like a cave) and means “hollow or round inward like the inside of a bowl”. convex since vexatious in it (because it is upset that the word is difficult to remember), and means “curved or rounded outward.”
There are no particularly recent words; concave has been in English since the 15th century, and rough since the 16th.
Make an empty silver box, in the style of a concave glass, whose exterior is worked with the art of exotic sauces, not only for decoration but also to create light.— Jean Taisnier, A much needed and beneficial book on navigation1575
If it’s convex or rounded outward, the best way to measure the width is with two gauges: but if it’s hollow inward, then you must measure no further from your base to the right line running between the ends of the suggested.— Thomas Hood, The use of two mathematical tools, crosse staffe and Iacobs staffe 1596
Each of these words has many meanings, but we are pretty sure that the reason most people look them up is simply because they have trouble remembering which words bow and which words bow. Sometimes silly little mnemonics are the best tools for the job.
Categories: Usage Notes
Source: vothisaucamau.edu.vn
