1 pipeline, tube, duct, hose, line, main, conduit, passage, conveyor, channel:
The pipes are inspected regularly for corrosion.
2 briar, meerschaum, corn-cob, calabash, clay pipe, water-pipe, hookah, narghile, chibouk or chibouque, peace-pipe or pipe of peace or calumet, Colloq Irish briar, Brit hubble-bubble, US bong:
He slowly tamped down the tobacco in his pipe, then lit it.
3 pan-pipe, whistle, boatswain's pipe, tooter, horn, wind, wind instrument, woodwind, brass:
They play the pipes in the London Symphony.
4 tootle, tweet, skirl, warble, whistle, peep, cheep:
One was piping away on a flute, the other was dancing a jig.
5 transmit, deliver, channel, conduct, convey, supply:
The gas is piped directly into our homes.
6 US look at, notice, spot, note, look at, Colloq get a load of:
Pipe the guy trying to climb up the outside of that building.
7 pipe down. become quieter, quieten down, make less noise, hush (up), shush (up), whisper, Colloq belt up, shut up:
I wish they'd pipe down, I can't sleep.
8 pipe up. speak (up), say, raise one's voice, make oneself heard, offer, volunteer:
Sally piped up with the correct answer from the back of the classroom.