A solid disk or cylinder that fits inside a hollow cylinder, and moves under pressure (as in an engine) or displaces fluid (as in a pump)
A valve device in some brass instruments for changing the pitch
To move up and down or in and out like a piston.
(infl of)
(l)
contact, connection
(ux)
(l).
(syn)
(l)
piston
(R:cy:GP)