| 释义 |
WordReference Random House Learner's Dictionary of American English © 2024so•di•um /ˈsoʊdiəm/USA pronunciation n. [uncountable]- Chemistrya soft, silver-white, chemically active metallic element that occurs naturally only in combination.
WordReference Random House Unabridged Dictionary of American English © 2024so•di•um (sō′dē əm),USA pronunciation n. - Chemistrya soft, silver-white, metallic element that oxidizes rapidly in moist air, occurring in nature only in the combined state, and used in the synthesis of sodium peroxide, sodium cyanide, and tetraethyllead: a necessary element in the body for the maintenance of normal fluid balance and other physiological functions. Symbol: Na;
at. wt.: 22.9898;
at. no.: 11;
sp. gr.: 0.97 at 20°C. - Biochemistry, Medicine, Drugs[Med., Pharm.]any salt of sodium, as sodium chloride or sodium bicarbonate, present in or added to foods or beverages as a seasoning or preservative and used in many pharmaceutical products as an antacid, anticoagulant, or other agent.
- Neo-Latin; see soda, -ium
- 1800–10
Collins Concise English Dictionary © HarperCollins Publishers:: sodium /ˈsəʊdɪəm/ n - a very reactive soft silvery-white element of the alkali metal group occurring principally in common salt, Chile saltpetre, and cryolite. Sodium and potassium ions maintain the essential electrolytic balance in living cells. It is used in the production of chemicals, in metallurgy, and, alloyed with potassium, as a cooling medium in nuclear reactors. Symbol: Na; atomic no: 11; atomic wt: 22.989768; valency: 1; relative density: 0.971; melting pt: 97.81±0.03°C; boiling pt: 892.9°C
- (as modifier): sodium light
Etymology: 19th Century: New Latin, from soda + -ium |