Merrick is a hamlet and census-designated place (CDP) in the Town of Hempstead in Nassau County, New York, United States. As of the 2010 census, the CDP population was 22,097. The name Merrick is taken from the word Meroke (oyster bed), the name of the ancestral homeland of the Algonquian tribe formerly indigenous to the area. It is served by the Merrick station on the Long Island Rail Road on the Babylon line.
According to the United States Census Bureau, the CDP has a total area of 5.2 square miles (13 km2), of which 4.2 square miles (11 km2) is land and 1.0 square mile (2.6 km2), or 19.27%, is water.
As of the census of 2000, there were 22,764 people, 7,524 households, and 6,478 families residing in the CDP. The population density was 5,423.3 per square mile (2,092.7/km²). There were 7,602 housing units at an average density of 1,811.1/sq mi (698.8/km²). The racial makeup of the CDP was 95.18% White, 0.56% African American, 0.10% Native American, 2.24% Asian, 0.01% Pacific Islander, 0.94% from other races, and 0.98% from two or more races.
There were 7,524 households out of which 42.9% had children under the age of 18 living with them, 76.0% were married couples living together, 7.6% had a female householder with no husband present, and 13.9% were non-families. 11.6% of all households were made up of individuals and 6.6% had someone living alone who was 65 years of age or older.