up·​stream | \ ˈəp-ˈstrēm How to pronounce upstream (audio) \

Definition of upstream

1 : in the direction opposite to the flow of a stream
2 : in or to a position within the production stream closer to manufacturing processes make most of its money upstream, selling cheap crude … to refineries— John Quirt
3 biochemistry : toward the beginning of a series of cellular processes : preceding a linked molecular event occurring in a sequence Many signaling pathways possess intrinsic negative feedback by which a downstream event in a pathway turns off an upstream event.— Harvey Lodish et al.

Examples of upstream in a Sentence

Recent Examples on the Web

The other option is trapping the fish and hauling them upstream via barges, trucks or sometimes helicopters, an expensive and resource intensive solution that often leaves fish disoriented. Jason Daley, Smithsonian, "Here’s How That Internet-Famous ‘Fish Tube’ Works," 15 Aug. 2019 The grandest coulee One way to explore coulee country is to head upstream from the Gorge Amphitheatre along the route of the Ice Age floods. John Nelson, Los Angeles Times, "The Ice Age gives birth to a wine and adventure age in Washington state," 20 July 2019 The races end 7½ miles upstream at the Washington Street Bridge in Hanover. Globe Staff, BostonGlobe.com, "Remembering Woodstock, 50 years on, at The Cabot," 7 July 2019 Rivers and streams that usually drain into the ocean can get clogged farther upstream, forcing water levels to rise. Nicole Chavez, CNN, "Rising water poses the deadliest threat in major storms -- and New Orleans is already flooded," 11 July 2019 One arm is raised as if in a wave to Sevnica, her hometown, about 5 miles upstream. Palko Karasz, BostonGlobe.com, "Melania Trump gets a statue near her hometown, carved by chain saw," 6 July 2019 The Minnesota Buffalo-Red River board has jurisdiction over impacts from the project within its district, which includes Clay and Wilkin counties, areas upstream from the dam that will be affected by pooling water. Forum News Service, Twin Cities, "Fargo-Moorhead flood-control project hits another obstacle as local permit is denied," 25 June 2019 Moccasin Creek overtopped a concrete diversion barrier upstream, sending floodwater, mud, trees and logs pouring into the reservoir. Peter Fimrite, SFChronicle.com, "Moccasin Dam, which came close to failure last year, is repaired and working," 10 June 2019 The Snake River sockeye will swim more than 900 miles upstream to a chain of subalpine lakes in the Sawtooth Mountains of central Idaho, the longest salmon migration in the contiguous United States. Corey Arnold, National Geographic, "Why wild salmon remains king in the Pacific Northwest," 27 Mar. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'upstream.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of upstream

1681, in the meaning defined at sense 1

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Last Updated

2 Sep 2019

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Time Traveler for upstream

The first known use of upstream was in 1681

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More Definitions for upstream



English Language Learners Definition of upstream

: in the direction opposite to the flow in a stream, river, etc. : toward the source of a stream, river, etc.


up·​stream | \ ˈəp-ˈstrēm How to pronounce upstream (audio) \

Kids Definition of upstream

: at or toward the beginning of a stream She rowed upstream.
up·​stream | \ ˈəp-ˈstrēm How to pronounce upstream (audio) \

Medical Definition of upstream

1 : in a direction along a molecule of DNA or RNA opposite to that in which transcription and translation take place and toward the end having a phosphate group attached to the position labeled 5′ in the terminal nucleotide … stretches of DNA upstream of genes—are known as promoters.— Matt Ridley, Time, 2 June 2003 — compare downstream sense 1
2 : toward the beginning of series of cellular processes : preceding a linked molecular event occurring in a sequence It's equally important to focus on additional mechanisms that are upstream of amyloid formation and mechanisms downstream that are involved in the actual degenerative processes within neurons.— Marc Tessier-Lavigne, quoted in Science, 17 Sept. 2010

More from Merriam-Webster on upstream

Rhyming Dictionary: Words that rhyme with upstream

Spanish Central: Translation of upstream

Nglish: Translation of upstream for Spanish Speakers

Comments on upstream

What made you want to look up upstream? Please tell us where you read or heard it (including the quote, if possible).


readily or continually undergoing change

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