Here's a basic definition of terms and canal-related words.
20th century Barge Canal – The currently operational New York State Canal System, completed in 1918. Successor to the towpath-era canal system. (see below: New York State Canal System)
canal system – An artificial waterway constructed for navigation, irrigation, or water power.
canalized – To convert to a canal. Refers to modified river and lake sections of the NYS Canal System (Barge Canal), such as the Mohawk and Seneca Rivers. See also “riverways,” below.
Clinton's Ditch – Nickname for the original Erie Canal, which opened in 1825.
enlarged canal system – The towpath-era canal system that was modified during the years 1835-1862, including the Enlarged Erie Canal, Enlarged Champlain Canal, Enlarged Oswego Canal, and Enlarged Cayuga-Seneca Canal.
Erie Canal – Refers to the main line of the 20th century Barge Canal or towpath-era Erie Canal that ran from Albany to Buffalo.
feeder (also “feeder canal”) – Any artificial channel built to supply water to the navigable canal system. Feeders enter the canal system at or near a summit level. Several feeders (e.g., Fayetteville, Chittenango, Oneida, Glens Falls) were navigable themselves.
land cuts – Those sections of the canal system that were excavated, as opposed to canalized sections or riverways. Nearly all of the towpath-era canal system consisted of land cuts; in the 20th century Barge Canal, the western Erie and northern Champlain are land cuts.
lateral (also “lateral canal”) – Refers to any navigable part of the 20th century Barge Canal other than the Erie Canal – i.e., the Champlain, Oswego, and Cayuga-Seneca Canals. Some discontinued laterals of the towpath-era canal system – namely, the Black River and Chenango Canals – have been retasked as feeders for the 20th century Barge Canal.
lock – A device used to lift or lower boats from one water level to another. Locks are used in most canals to bypass waterfalls, rapids, dams, and other obstacles to navigation. A typical lock consists of a chamber with gates at both ends: a boat enters through the gates at one end of the lock; the gates are closed; water is added to or released from the chamber through valves until it reaches the level at the other end of the lock; the gates at that end are opened; and the boat continues on its way. Locks on the New York State Canal System today are 310 feet long, 45 feet wide, and electrically operated.
New York State Canal System – The official name of the currently operational canal system, also known as the Barge Canal. Includes the Erie Canal, Champlain Canal, Oswego Canal, and Cayuga-Seneca Canal.
prism – The man-made channel that carries canal water; essentially, a large ditch – hence the name “Clinton's Ditch”.
riverways – The canalized sections of the canal system.
summit level – A high point where a canal crosses between two drainage basins; water drains away from a summit level in two directions. There is a summit level on the Erie Canal between locks E20 and E21 near Rome that drains west toward Lake Ontario and east toward the Hudson River.
towpath – A path alongside a canal used by horses or mules towing boats by means of a rope (“towrope”). Many towpaths along abandoned canals have been converted into recreational trails.
towpath-era canal system – Refers to the predecessors of the 20th century Barge Canal – both the original system, built 1817-1825, and the enlarged system, built 1835-1862 – in which mules or horses towed canalboats. The 20th century Barge Canal (opened in 1918) does not require towpaths - canalboats operate under their own power or are pushed or pulled by tugboats.