Arcaicam Esperantom

Arcaicam Esperantom (English: Archaic Esperanto; Esperanto: arĥaika Esperanto, arkaika Esperanto), is a constructed auxiliary sociolect for translating literature into Esperanto created to act as a fictional 'Old Esperanto', in the vein of languages such as Middle English or the use of Latin citations in modern texts.

It was created by linguist Manuel Halvelik as part of a range of stylistic variants including Gavaro (slang) and Popido (patois), forming Serio La Sociolekta Triopo.

Halvelik also compiled a scientific vocabulary closer to Greco-Latin roots and proposed its application to fields such as taxonomy and linguistics. He gave this register of Esperanto the name Uniespo (Uniëspo, Universala Esperanto, 'Universal Esperanto').

The idea of an "old Esperanto" was proposed by the Hungarian poet Kálmán Kalocsay who in 1931 included a translation of the Funeral Sermon and Prayer, the first Hungarian text (12th century), with hypothetic forms as if Esperanto were a Romance language deriving from Vulgar Latin.