Cypress was originally nicknamed "Waterville" due to the preponderance of artesian wells in the area, but was incorporated under the name Dairy City in 1956 by local dairy farmers as a means of staving off developers and to preserve their dairies, much like the then-neighboring cities of Dairy Valley in Cerritos and Dairyland in La Palma. However, after World War II,the land became too valuable for farming or ranching, and the dairiesgradually sold out to housing developers during the 1960s, so that bythe 1970s, no dairies remained. Many of the dairymen moved theiroperations to Chino, where development is once again pushing them out of the area.
In 1957, local residents voted to change the name of Dairy City to "Cypress". The name was taken from Cypress Elementary School, originally built in 1895, which took its name from the Cypress trees planted to protect the schoolhouse from the seasonal Santa Ana winds. Cypress Elementary School also provided the name for new Pacific Electric Railroadstation on Walker Street at Lincoln Avenue when the Santa Ana Line wascompleted in 1906, as "Waterville" had already been used elsewhere in the system