ポタシウムポタシウムMeanings1nounpotassiumrare termRare term for potassium; almost always replaced by カリウム in modern Japanese. May appear in older scientific texts or as a stylistic variant.See also: カリウム古ふるい化か学がくの本ほんには「ポタシウム」と書かいてあることがある。In old chemistry books, it is sometimes written as ポタシウム.