Terryville is a census-designated place (CDP) in Litchfield County, Connecticut, United States, and is a village of the Town of Plymouth, Connecticut. The population was 5,360, at the 2000 census. The village is named for Eli Terry Jr.,the son of the well-known clockmaker Eli Terry Sr.. Terryville is also home to the Lock Museum of America. There is an old water wheel in downtown Terryville.
According to the United States Census Bureau, the CDP has a total area of 7.3 km² (2.8 mi²). 7.2 km² (2.8 mi²) of it is land and 0.1 km² (0.04 mi²) of it (1.07%) is water.
As of the census of 2000, there were over 5,360 people, 2,199 households, and 1,460 families residing in the CDP. The population density was 747.1/km² (1,935.6/mi²). There were 2,312 housing units at an average density of 322.3/km² (834.9/mi²). The racial makeup of the CDP was 97.18% White, 0.86% African American, 0.15% Native American, 0.41% Asian, 0.30% from other races, and 1.10% from two or more races. Hispanic or Latino of any race were 1.18% of the population.