STOPCOCK
stopcock, cock, turncock
(noun) faucet consisting of a rotating device for regulating flow of a liquid
Source: WordNet® 3.1
Etymology
Noun
stopcock (plural stopcocks)
A valve, tap or faucet which regulates the flow of liquid or gas through a pipe.
(British) A main shutoff for water to a home from a municipal supply. Usually these valves exist in pairs, one outside the property boundary and one inside the property boundary.
Source: Wiktionary
Stop"cock`, n.
1. A bib, faucet, or short pipe, fitted with a turning stopper or
plug for permitting or restraining the flow of a liquid or gas; a
cock or valve for checking or regulating the flow of water, gas,
etc., through or from a pipe, etc.
2. The turning plug, stopper, or spigot of a faucet. [R.]
Source: Webster’s Unabridged Dictionary 1913 Edition