Proto-Esperanto (Esperanto: pra-Esperanto) is the modern term for any of the stages in the evolution of L. L. Zamenhof's language project, prior to the publication of his Unua Libro in 1887.
Proto-Esperanto (Esperanto: pra-Esperanto) is the modern term for any of the stages in the evolution of L. L. Zamenhof's language project, prior to the publication of his Unua Libro in 1887.