Ido

Ido is a constructed international auxiliary language that began in 1907 as a reform of Esperanto, adopted by the Delegation for the Adoption of an International Auxiliary Language meeting in Paris — the name is simply Esperanto for 'offspring'. Its architects, chiefly the French logician Louis Couturat and the Esperantist Louis de Beaufront, aimed at greater naturalness and printability: the accented letters ĉ ĝ ĥ ĵ ŝ ŭ were abolished, obligatory adjective agreement and the accusative -n were dropped, and many roots were reselected for wider international recognisability. The grammar keeps Esperanto's transparent endings — nouns in -o, adjectives in -a, adverbs in -e, infinitives in -ar — with stress on the penultimate syllable except in infinitives, which stress the last. The reform split the Esperanto movement bitterly and Ido never displaced its parent, but it has been maintained continuously ever since, today by the Uniono por la Linguo Internaciona Ido, with estimates of roughly one to five thousand users and an active Wikipedia.