area

词源: 'piece of flat ground'

柯林斯:
1. The area/dialling code for a city or region is the series of numbers that you have to dial if you are making a telephone call from a different area.
2. The catchment area of a school, hospital, or other service is the area that it serves.
3. In geography, the catchment area of a river is the area of land from which water flows into the river.
4. A conservation area is an area where birds and animals are protected, or an area where old buildings are protected.
5. A disaster area is a part of a country or the world which has been very seriously affected by a disaster such as an earthquake or a flood.
6. If you refer to something as a grey area, you mean that it is unclear, for example because nobody is sure how to deal with it or who is responsible for it, or it falls between two separate categories of things.
7. If you refer to a place as a no-go area, you mean that it has a reputation for violence and crime which makes people frightened to go there, or a place which is controlled by a group of people who use force to prevent other people from entering it.
8. In football, the penalty area/box is the rectangular area in front of the goal. Inside this area the goalkeeper is allowed to handle the ball, and if the defending team breaks a rule here, the opposing team gets a penalty.
9. A rest/service area is a place beside a motorway or freeway where you can buy petrol and other things, or have a meal.
10. If part of a country that is involved in a war is declared to be a safe area, neutral forces will try to keep peace there so that it is safe for people.
11. An Air Defense Identification Zone (ADIZ) is airspace over land or water in which the identification, location, and control of civil aircraft is required in the interest of national security.
12. A "no-fly zone" could be placed over Windsor Castle as its security arrangements are reviewed, the Metropolitan Police said.

A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building.[1] By contrast, a wide area network (WAN) not only covers a larger geographic distance, but also generally involves leased telecommunication circuits. Ethernet and Wi-Fi are the two most common technologies in use for local area networks.

In math, the area of a shape can be measured by comparing the shape to squares of a fixed size. There are several well-known formulas for the areas of simple shapes such as triangles, rectangles, and circles. Using these formulas, the area of any polygon can be found by dividing the polygon into triangles. For shapes with curved boundary, calculus [微积分] is usually required to compute the area. Indeed, the problem of determining the area of plane figures was a major motivation for the historical development of calculus.

Heron (or Hero) of Alexandria found what is known as Heron's formula for the area of a triangle in terms of its sides, and a proof can be found in his book, Metrica, written around 60 CE. It has been suggested that Archimedes [阿基米德] knew the formula over two centuries earlier. A formula equivalent to Heron's was discovered by the Chinese independently of the Greeks. It was published in 1247 in Shushu Jiuzhang ("Mathematical Treatise [专题论文] in Nine Sections"), written by Qin Jiushao. Heron of Alexandria or Hero, mathematician and inventor. The dates of his birth and death are unknown; conjecture places them between the 2d cent. B.C. and the 3d cent. A.D. He is believed to have lived in Alexandria; although he wrote in Greek, his origin is uncertain.

area最泛指。region通常指地理上有天然界限或具有某种特色。district通常指行政分区。zone通常指有特定的功能。[百度知道]

六级/考研单词: dial, geography, affection, earthquake, gray, repute, fright, soccer, motorway, gasoline, neutral, nationwide, metropolitan, mathematics, triangle, curve, compute, motive, equivalent

海伦公式_百度百科 (baidu.com)