ENGLISH
REFERENCE

upstream

adj. · adv. · v.
US //ˈəpˈstɹim// UK //ʌpstɹˈiːm// up·stream
  1. 1 against the water flow (adj.)
    B2 Upper Intermediate

    located or moving in the opposite direction to the way a river or stream flows.

    situated or moving in a direction contrary to the flow of a current or stream.

    Example

    The salmon swim upstream for many miles to reach their spawning grounds.

    Example

    The researchers took water samples from an upstream location to ensure the data wasn't contaminated by the factory's waste pipe further down.
    • upriver
  2. 2 earlier in a process (adj.)
    C1 Advanced Academic Technical

    happening at an earlier stage in a process, such as the start of a production line.

    relating to the earlier stages of a process, particularly in industrial production, supply chains, or biological pathways.

    Example

    The company is investing in upstream activities like oil exploration and drilling.

    Example

    By addressing the problem at an upstream stage of the manufacturing process, the engineers prevented a series of defects in the final product.

    Usage

    Often used in business to refer to the extraction of raw materials.
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  1. 3 moving upriver (adv.)
    B2 Upper Intermediate

    moving against the current of a river.

    in a direction against the flow of a stream or current.

    Example

    It is much harder to row upstream than it is to go with the current.

    Example

    The barge struggled to move upstream against the heavy spring floods, requiring additional tugboats to maintain its course.
    • upriver
  2. 4 software development (v.)
    C1 Advanced Technical Computing

    to send a software update back to the original creators so they can include it in the main version.

    to submit a software patch or feature to the original developers or maintainers of a project for inclusion in the primary source code.

    Example

    The developer decided to upstream her bug fixes to the main Linux project.

    Example

    The team worked hard to upstream their security patches, ensuring that the entire community would benefit from the improved code in the next release.
Origin

From up- + stream.

Idioms1 entry

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