Four"-way` (?), a. Allowing
passage in either of four directions; as, a four-way cock, or
valve. Francis.
Four-way cock, a cock connected with four
pipes or ports, and having two or more passages in the plug, by which
the adjacent pipes or ports may be made to communicate; formerly used
as a valve in the steam engine, and now for various other purposes.
In the illustration, a leads to the upper end of a steam
engine cylinder, and b to the lower end; c is the steam
pipe, and d the exhaust pipe.