Learn how to say Esperantist correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word Esperanto:
an artificial language devised in 1887 as an international medium of communication, based on roots from the chief European languages. It retains the structure of these languages and has the advantage of grammatical regularity and ease of pronunciation.
late 19th century: from the name Dr Esperanto, used as a pen name by the inventor of the language, Ludwik L. Zamenhof (1858–1917), Polish physician; the literal sense is ‘one who hopes’ (based on Latin sperare ‘to hope’)