a tube through which liquids or gases can flow
passage, tube
Cases of word usage
1) calibre; the inside diameter of a pipe etc (caliber)
2) a union of two vowel sounds or vowel letters e.g. as in pipe /paip/ (diphthong)
3) (a pipe in an engine or machine for) gas, steam, vapour etc that is no longer wanted (exhaust)
4) a pipe used for carrying heat or smoke away from a boiler etc (flue)
5) (of an engine, pipe etc) to become filled with ice and not work (freeze up)
6) a long semi-circular pipe fixed under the edge of a roof to carry away rainwater; a long deep channel at the side of a road for rainwater (gutter)
7) a pipe for water (especially in a street) with a place where a hose can be attached (hydrant)
8) a short coat with sleeves; an outer covering round a tank, pipe etc; a skin (of a potato) (jacket)
9) very, high; a length of pipe (piping)
10) an implement used for clearing a blocked pipe by suction (plunger)