köken: Etymology tree French horizontalbor. Proto-Indo-European *-nós Proto-Balto-Slavic *-inas Proto-Slavic *-ьnъ Old Polish -ny Polish -ny Polish horyzontalny From French horizontal + Polish -ny.
köken: Created during the Hungarian language reform, which took place in the 18th–19th centuries. The neologists created it from the adverb vízszint (“horizontally”) + -es (adjective-forming suffix). The adverb vízszint is a lexicalization of the former noun phrase víz szint (“on the surface of water”), from víz (“water”) + szín (“surface”) + -t (locative suffix).