The Collaborative International Dictionary of English v.0.48:

pipeline \pipeline\, pipe line \pipe line\
   1. A line of pipe with pumping machinery and apparatus for
      conveying liquids, gases, or finely divided solids, such
      as petroleum or natural gas, between distant points.
      [Webster 1913 Suppl. +PJC]

   2. fig. an information channel direct from the source.
      [PJC]

   3. the set of stages and processes from the invention or
      design of a product to its ultimate use, production, or
      commercial sale. Used commonly in the phrase

   in the pipeline, i. e. still in preparation or under
      development.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Pipe-line \Pipe"-line`\, v. t.
   To convey by a pipe line; to furnish with a pipe line or pipe
   lines.
   [Webster 1913 Suppl.]

Moby Thesaurus II by Grady Ward, 1.0:

67 Moby Thesaurus words for "pipeline":
   adjutage, bush telegraph, catheter, channel, coming, conduit,
   confidential information, connection, contact, conveyor, cooking,
   drainpipe, duct, efflux tube, fire hose, flue pipe, flume, funnel,
   garden hose, gas pipe, grapevine, grapevine telegraph, hose,
   hosepipe, imminent, in the offing, in the works, inside dope,
   inside information, insider, line, main, nipple, on the way,
   organ pipe, origin, passage, pipe, pipette, piping,
   put through channels, ready, reed, reed pipe, siamese,
   siamese connection, siphon, snorkel, soil pipe, source, standpipe,
   steam pipe, stem, straw, supplier, tap, the lowdown, tube, tubing,
   tubulation, tubule, tubulet, tubulure, under way, waste pipe,
   water pipe, wellspring