up·​stream | \ ˈəp-ˈstrēm \

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 Pentagon began to realize that the Chinese were going upstream ahead of our current technology and trying to purchase -- succeeding in purchasing the technology to produce weapons and win wars 10 or 15 years from now. Fox News, "Has China been duping the US for nearly half a century?," 13 Aug. 2018 Trout anglers can expect the fish to gradually move upstream to similar, cold-water refuges. Rocky Barker, idahostatesman, "Northwest rivers are warming. And that may threaten your favorite fishing spot | Idaho Statesman," 7 May 2018 On the Rogue, those three designations cover 84.5 miles from the mouth of the Applegate River to Lobster Creek about 16 river miles upstream of the Pacific. Mark Freeman, The Seattle Times, "Man visiting 58 Oregon rivers for law’s anniversary," 30 June 2018 Currents near waterfalls can be extremely swift, even in areas farther upstream. Joe Marusak, charlotteobserver, "NC mountain visitors warned of toppling trees, as part of Blue Ridge Parkway reopens," 4 June 2018 Much of the damage was a result of flooding from the nearby Patapsco River, the flow of which is regulated by Liberty Reservoir (approximately 18 miles upstream). baltimoresun.com, "Ellicott City flooding by the numbers," 29 May 2018 Before dams were built, paddlefish were highly migratory, often swimming hundreds of miles upstream to spawn. New York Times, "Hooking the Dinosaur of Fish," 26 May 2018 Both proponents and detractors agree that raising the dam would back up the McCloud farther upstream, inundating some of the land along the river for weeks or months at a time. Ryan Sabalow And Dale Kasler, sacbee, "This one stretch of river could decide the future of Shasta Dam | The Sacramento Bee," 7 May 2018 Many days of rain had swollen the Potomac River to near-flood stage at Little Falls and flooded other areas upstream and downstream from Great Falls, including the Tidal Basin. Kevin Ambrose, Washington Post, "Raging water at Great Falls, flooding at the Tidal Basin after last week’s deluge," 21 May 2018

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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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 \

Kids Definition of upstream

: at or toward the beginning of a stream She rowed upstream.
up·​stream | \ ˈəp-ˈstrēm \

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

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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

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