The definition of potassium is an alkali metal.
An example of potassium is the mineral found in dried apricots and raisins.
See potassium in Webster's New World College Dictionary
Origin: ModL: so named (1807) < potassa < Du potasch, potash, by Humphrey Sir Humphry Davy, who first isolated it from potash
See potassium in American Heritage Dictionary 4
noun Symbol K
Origin: From potash (from which it was first obtained).
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