Definition of "upstream"

In a direction against the flow of a current or stream of fluid (typically water); upriver.  examples

(figurative) Occurring earlier than something else; (also, usually, especially) being an influence on something else; causing a consequence for something else.

1. (oil industry) Involving exploration and pre-production rather than refining and selling.  examples

2. (computer networking) In the direction from the client to the server.  examples

3. (open-source software) Maintained, owned, or associated with the original developers of the given software; in contrast to a modified version downstream.  quotations  examples

   Quotations

   • You can also check the upstream and/or Debian bug trackers for open and closed bugs and the upstream revision history or newer release(s).

     2013, Matthew Helmke, Ubuntu Unleashed 2013 Edition: Covering 12.10 and 13.04, Pearson Education

   • If the developer knows the bug is an upstream bug but does not know which bug it is in the upstream bug tracker, he can add an upstream task to the bug report.

     2012, Jono Bacon, The Art of Community: Building the New Age of Participation, O'Reilly Media, Inc., page 141

   • Because a user generally does not know the pedigree of the open source, it cannot know whether an upstream developer used intellectual property belonging to a third party in developing that software.

     2008, Michael Dennis Scott, Scott on Outsourcing: Law and Practice, Aspen Publishers, page 198

   • We'll walk through the steps to build FreeS/WAN using the upstream tarball.

     2002, Tony Mancill, Linux Routers: A Primer for Network Administrators, Prentice Hall, page 190

4. (biology) Towards the leading end (5′ end) of a DNA molecule.

Against the current.  quotations  examples

(intransitive) To stream upward.  examples

(transitive, open-source software) To have (a software library, patch, etc.) accepted by the original developers of the related software, so that they maintain and distribute it.  examples

Part of the river towards the upstream direction.  quotations  examples

(open-source software) The original developers or maintainers of software.  examples