West Nyack is a hamlet and census-designated place in the town of Clarkstown, Rockland County, New York, United States. It is located north of Blauvelt, east of Nanuet, southwest of Valley Cottage, southeast of Bardonia, and west of Central Nyack. It is approximately 18 miles (29 km) north of New York City. The population was 3,439 at the 2010 census.
In 1847, the hamlet was named Clarksville, renamed MontMoor, and since 1891 has been known as West Nyack.
West Nyack is located at 41°5′28″N 73°58′8″W (41.091096, -73.968785).
According to the United States Census Bureau, the CDP has a total area of 2.9 square miles (7.5 km2), all land.
As of the census of 2000, there were 3,282 people, 1,107 households, and 892 families residing in the CDP. The population density was 1,125.9 per square mile (435.5/km2). There were 1,132 housing units at an average density of 388.3/sq mi (150.2/km2). The racial makeup of the CDP was 88.03% White, 1.98% African American, 0.03% Native American, 7.59% Asian, 0.98% from other races, and 1.40% from two or more races. Hispanic or Latino of any race were 5.58% of the population.
There were 1,107 households, out of which 36.7% had children under the age of 18 living with them, 70.8% were married couples living together, 6.9% had a female householder with no husband present, and 19.4% were non-families.