THESAURUS
Valve
aerophone, ball cock, ball valve, bell, bung, bunghole, check valve, cock, cork, discharge tube, double reed, drain cock, draw cock, embouchure, faucet, gate, horn, key, lid, lip, mouthpiece, needle valve, peg, petcock, pin, pipe, plug, radio tube, reed, sea cock, slide, spigot, spike, spile, spill, stop, stopcock, stopgap, stopper, stopple, tap, tooter, tube, vacuum tube, valvula, valvule, wind, wind instrument
ROGET THESAURUS
Valve
Stopper
N
stopper, stopple, plug, cork, bung, spike, spill, stopcock, tap, rammer, ram, ramrod, piston, stop-gap, wadding, stuffing, padding, stopping, dossil, pledget, tompion, tourniquet, cover, valve, vent peg, spigot, slide valve, janitor, doorkeeper, porter, warder, beadle, cerberus, ostiary.
Conduit
N
conduit, channel, duct, watercourse, race, head race, tail race, abito, aboideau, aboiteau, bito, acequia, acequiador, acequiamadre, arroyo, adit, aqueduct, canal, trough, gutter, pantile, flume, ingate, runner, lock-weir, tedge, vena, dike, main, gully, moat, ditch, drain, sewer, culvert, cloaca, sough, kennel, siphon, piscina, pipe, funnel, tunnel, water pipe, waste pipe, emunctory, gully hole, artery, aorta, pore, spout, scupper, adjutage, ajutage, hose, gargoyle, gurgoyle, penstock, weir, flood gate, water gate, sluice, lock, valve, rose, waterworks, pipeline, vascular.