Plainview is a hamlet and census-designated place (CDP) located near the North Shore of Long Island in the town of Oyster Bay, Nassau County, New York, United States. The population of the CDP as of 2010 was 26,217.
Plainview's origins dates to 1648, when Robert Williams, a settler from Wales, bought land in the area. The land was considered desirable for farming because of a small pond named the Moscopas by local Native Americans, meaning "hole of dirt and water". The remainder of the land in the area was purchased by Thomas Powell in 1695 as part of the Bethpage Purchase. The name "Mannatto Hill" had already appeared on the 1695 deed of the Bethpage Purchase, and the settlement came to be called "Manetto Hill".Manitou was the Native American word either for "god" or for "spirit".The 1837 arrival of the Long Island Rail Road to nearby Hicksville brought a boom to local farming. In 1885, residents of Manetto Hill petitioned the United States Postal Service for a local post office, but were turned down because, according to several accounts, a similar name was already in use upstate. The hamlet was then named "Plainview", for the view of the Hempstead Plains from the top of the Manetto Hills.