from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A principal section of a railroad line.
  • noun Slang A principal and easily accessible vein, usually in the arm or leg, into which a drug can be injected.

from the GNU version of the Collaborative International Dictionary of English.

  • noun Ahe principal route of a transportation system, such as a railroad or bus line.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The principal route or line of a railway.
  • noun fishing In longline fishing the central line to which the branch lines with baits are attached.
  • noun slang A principal vein into which a drug can be injected.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun the principal route of a transportation system


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