Potasio is the “Spanishized” version of scientific Latin potassium, the form that English uses unchanged as the name of chemical element number 19. English had previously used the form potass, from French potasse. French had taken the word from Dutch potas, a compound of pot, which means the same as the identical English word, and as, which is a cognate of English ash. In fact English has the corresponding compound potash, a singular that was copied from the Dutch plural potaschen. Pot ashes, you see, were people’s original source of potassium.
It’s not a coincidence that English pot resembles Spanish pote, whose meanings include ‘pot, jar, mug, jug.’ Spanish took the word from Catalan pot, which, like French and English pot, ultimately traces back to Vulgar Latin *pottus, for which no prior source is known. Spanish pote gave rise to the alternate form bote, which designates various containers, including ‘a can, a jar, a tin.’
Coming back to potasio/potassium, whose etymology is easy enough to trace, one question may come to mind for anyone who has taken an elementary chemistry class: how did K come to be the chemical symbol for potassium? According to answers.com, “The chemical symbol K comes from kalium, the Mediaeval Latin word for potash, which may have been taken from the Arabic word qali, meaning alkali.”
© 2014 Steven Schwartzman