euphemism [L16th] This word is from Greek eu ‘well’ and phēmē ‘speaking’ from phēnai ‘to speak’, which is also where prophet [ME] came from. Several other English words start with eu meaning ‘well’. The eucalyptus tree [E19th] is literally ‘well covered’: it is so called because the unopened flower is protected by a sort of cap. If you give a eulogy [LME] you praise, or speak well of, someone: the -logy part, found in a great many English words, comes from Greek logos ‘speech, word, reason’. If something is euphonious [L18th] it is pleasing to the ear: phōnē ‘sound’ is the Greek root (the mid 19th-century euphonium, which not everyone finds pleasing, comes from the same word). Finally, euthanasia [E17th] is literally ‘an easy death’: thanatos is ‘death’ in Greek. The euro- in Europe and related words is unconnected. Europe is from Europa, the name of a princess of Tyre, in modern-day Lebanon, who was admired by the god Zeus. He turned himself into a bull and swam across the sea to Crete with the princess on his back. Once in Crete Europa bore Zeus three sons, and eventually gave her name to the continent of Europe.