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pipe (pīp)
a. A hollow cylinder or tube used to conduct a liquid, gas, or finely divided solid.
b. A section or piece of such a tube.
a. A device for smoking, consisting of a tube of wood, clay, or other material with a small bowl at one end.
b. An amount of smoking material, such as tobacco, needed to fill the bowl of a pipe; a pipeful.
3. Informal
a. A tubular part or organ of the body.
b. pipes The passages of the human respiratory system.
4. Abbr. p.
a. A large wine cask, especially one having a capacity of 126 gallons or 2 hogsheads (478 liters).
b. This volume as a unit of liquid measure.
5. Music
a. A tubular wind instrument, such as a flute.
b. Any of the tubes in an organ.
c. pipes A small wind instrument, consisting of tubes of different lengths bound together.
d. pipes A bagpipe.
6. pipes Informal The vocal cords; the voice, especially as used in singing.
7. A birdcall.
8. Nautical A whistle used for signaling crew members: a boatswain's pipe.
9. Geology
a. A vertical cylindrical vein of ore.
b. One of the vertical veins of eruptive origin in which diamonds are found in South Africa.
10. Geology An eruptive passageway opening into the crater of a volcano.
11. Metallurgy A cone-shaped cavity in a steel ingot, formed during cooling by escaping gases.
v. piped, pip·ing, pipes
a. To convey (liquid or gas) by means of pipes.
b. To convey as if by pipes, especially to transmit by wire or cable: piped music into the store.
2. To provide with pipes or connect with pipes.
a. To play (a tune) on a pipe or pipes.
b. To lead by playing on pipes.
4. Nautical
a. To signal (crew members) with a boatswain's pipe.
b. To receive aboard or mark the departure of by sounding a boatswain's pipe.
5. To utter in a shrill reedy tone.
6. To furnish (a garment or fabric) with piping.
7. To force through a pastry tube, as frosting onto a cake.
8. Slang To take a look at; notice.
1. To play on a pipe.
2. To speak shrilly; make a shrill sound.
3. To chirp or whistle, as a bird does.
4. Nautical To signal the crew with a boatswain's pipe.
5. Metallurgy To develop conical cavities during solidification.
Phrasal Verbs:
pipe down Slang
To stop talking; be quiet.
pipe up
To speak up.

[Middle English, from Old English pīpe, from Vulgar Latin *pīpa, from Latin pīpāre, to chirp.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.