Papillion is a city in Sarpy County in the state of Nebraska, United States. Designated as the county seat, it developed as an 1870s railroad town and suburb of Omaha. The city is part of the larger five-county metro area of Omaha. Papillion's population was 18,894 at the 2010 census. Its growth since the late 20th century has reflected Omaha's.
The city was named after the creek of the same name which flows through its center; this had been named by early French explorers, as France had claimed this territory through the eighteenth century. The name Papillion is derived from the French term (papillon) for butterfly. According to local tradition, the early French explorers named the creek as Papillon because they saw so many butterflies along its grassy banks. The spelling was changed through a transliteration of the French word.
Papillion was platted in 1870 when the railroad was extended to that point.