indicator
英 ['?nd?ke?t?]
美['?nd?ket?]
- n. 指示器；[試劑] 指示劑；[計(jì)] 指示符；壓力計(jì)
英英釋意
- 1. a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time
- 2. a signal for attracting attention
- 3. a device for showing the operating condition of some system
- 4. (chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction