As if the oceans needed more terrible news, scientists have learned that the coral reefs surrounding the Florida Keys are dissolving. The culpritâocean acidificationâwasnât expected to start hitting reefs hard for another three decades.
index noun (LIST) C1 [ C ] an alphabetical list, such as one printed at the back of a book showing which page a subject, name, etc. is on: Try looking up heart disease in the index. âº [ C ] a collection of information stored on a computer or on a set of cards, in alphabetical order:
Notice the large dot-com spike on the NASDAQ, a result of the large number of technology companies on that index. A stock index or stock market index is a measurement of the value of a section of the stock market. It is computed from the prices of selected stocks (typically a weighted average). It is a tool used by investors and financial managers to describe the market, and to compare the return on specific investments. An index is a mathematical construct, so it may not be invested in directly.