potassium

n. (K) silver-white metallic element (Chemistry)

Potassium (IPA: ) is a chemical element. It has the symbol K ( → ) and atomic number 19. The name "potassium" comes from the word "potash", as potassium was first isolated from potash. Potassium is a soft silvery-white metallic alkali metal that occurs naturally bound to other elements in seawater and many minerals. It oxidizes rapidly in air and is very reactive, especially towards water. In many respects, potassium and sodium are chemically similar, although organisms in general, and animal cells in particular, treat them very differently.
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Potassium /po·tas·si·um/ chemical element, at. no. 19. Potassium is the chief cation of intracellular fluid, and many of its salts are used as [more]Potassium - Community and Resources

Noun
1. a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite
(synonym) K, atomic number 19
(hypernym) metallic element, metal
(substance-holonym) seawater, saltwater, brine

n. potassium, silver-white metallic element (Chemistry)