Hockanum is derived from the Native American Podunk people Algonquin language word meaning "hook-shaped", so named because of the course of the river.
It rises at the outlet of Shenipsit Lake in Rockville, then flows through Vernon, Ellington, Manchester, and East Hartford.
It begins at the bridge at Pleasant View Drive, one mile west of Vernon Center, and continues to the Connecticut River.
Historically used for industry, the river has in recent years had hiking trails and linear parks developed along its banks.
The banks of the river are slowly being cleaned up after years of pollution and dumping.