mass noun
1- the chemical element of atomic number 80, a heavy silvery-white metal which is liquid at ordinary temperatures. (Symbol: Hg)（化学元素）汞, 水银（符号： Hg）。亦称QUICKSILVER.
1.1
- the column of such metal in a thermometer or barometer, or its height as indicating atmospheric temperature or pressure水银柱：
the mercury rises, the skies steam, and the nights swelter.
水银柱升高, 天空多水汽, 晚间闷热。
1.2
- historical this metal or one of its compounds used medicinally, especially to treat syphilis〈史〉水银; 汞盐。
词源
Middle English: from Latin Mercurius （see sense 1 of MERCURY）.