a light silvery element of the alkali metal group that is highly reactive and rapidly oxidizes in air; occurs principally in carnallite and sylvite. It is used when alloyed with sodium as a cooling medium in nuclear reactors and its compounds are widely used, esp in fertilizers. Symbol: K; atomic no: 19; atomic wt: 39.0983; valency: 1; relative density: 0.862; melting pt: 63.71°C; boiling pt: 759°C
WordReference Random House Learner's Dictionary of American English © 2025
po•tas•si•um /pəˈtæsiəm/USA pronunciation
n. [uncountable]
WordReference Random House Unabridged Dictionary of American English © 2025- Chemistrya silvery white metallic element that burns rapidly in the air and whose compounds are used as fertilizer.
po•tas•si•um
(pə tas′ē əm),USA pronunciation n. [Chem.]
- Chemistrya silvery-white metallic element that oxidizes rapidly in the air and whose compounds are used as fertilizer and in special hard glasses. Symbol: K;
at. wt.: 39.102;
at. no.: 19;
sp. gr.: 0.86 at 20°C.
- Neo-Latin; see potassa, -ium
- 1800–10
Collins Concise English Dictionary © HarperCollins Publishers::
'potassium' also found in these entries (note: many are not synonyms or translations):
Gram's solution
- K
- Rochelle salt
- Seidlitz powder
- acid number
- aldosterone
- aldosteronism
- alkali
- alkali metal
- alkalic
- alum
- alunite
- amide
- amiloride
- antimonate
- antimony potassium tartrate
- antimonyl
- apophyllite
- argol
- atrial natriuretic factor
- aureolin
- benzoin
- black flux
- bromide
- calomel electrode
- carnallite
- carnotite
- caustic potash
- chlorite
- chromate
- chrome
- chrome alum
- cobalt yellow
- complete fertilizer
- cream of tartar
- cyanide
- cyanide process
- dibasic potassium phosphate
- dichromate
- dihydrate
- electrolyte
- ethylate
- feldspar
- ferricyanide
- ferrocyanide
- gelignite
- glauconite
- green soap
- gum bichromate process
- gunpowder