potion: [13] The Indo-European base *pō-, *pī- ‘drink’ has provided the verb for ‘drink’ in most modern European languages, apart from the Germanic ones: French boire, for instance, Russian pit’, and Welsh yfed all come from it. Amongst it Latin descendants were the nouns pōtiō ‘drink’, source of English potion (and also poison) and pōtus ‘drink’, the probable ancestor of English pot, and the verb pōtāre ‘drink’, from which English gets potable [16]. => poison, potable
potion (n.)
c. 1300, pocioun "medicinal drink," from Old French pocion "potion, draught, medicine" (12c.), from Latin potionem (nominative potio) "a potion, a drinking," also "poisonous draught, magic potion," from potus, irregular past participle of potare "to drink," from PIE root *po(i)- "to drink" (cognates: Sanskrit pati "drinks," panam "beverage;" Greek pinein "to drink," poton "that which one drinks," potos "drinking bout;" Old Church Slavonic piti "to drink," pivo "beverage"). Potus as a past participle adjective in Latin meant "drunken."