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pipe·line

(pīplīn′)

1. A long pipe, especially one used for the conveyance of water, gas, or petroleum products.

2. A channel by which information is privately transmitted.

3. A system through which something is conducted, especially as a means of supply: "Farther down the pipeline are three other approaches to vaccine development" (Boston Globe).

tr.v. pipe·lined, pipe·lin·ing, pipe·lines

1. To convey by or as if by a system of pipes.

2. To lay a system of pipes through.

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pipeline

Trans-Alaska Pipeline System, Alaska

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.

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