adverb or adjective
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 Further upstream, there are production cutbacks in countries like China, which has been grappling with a far-reaching power shortage. Daniel Funke, USA TODAY, 27 Oct. 2021 The best spots are at the edge of the channel of the Tule River, upstream at the convergence with the Fall River and in the vicinity of Big Lake Springs. Tom Stienstra, San Francisco Chronicle, 8 July 2021 Gustaveson took a visitor on a trip around the lake's shoreline just upstream from Glen Canyon Dam and pointed to a sandstone outcropping., 2 Sep. 2021 His favorite stretch of water is Cataract Canyon, just upstream from Glen Canyon. Elizabeth Kolbert, The New Yorker, 9 Aug. 2021 The first-ever emergency release of water from dams upstream of Lake Powell began last month, but it isn’t expected to significantly raise lake levels. Zak Podmore, The Salt Lake Tribune, 7 Aug. 2021 These massive rocks, the team concluded, must have come from outside the crater, and was likely part of bedrock located on the crater rim or else 40 or more miles upstream. David Bressan, Forbes, 9 Oct. 2021 Though the flowing water appears entirely natural, Silver noted that Sierra Vista’s wastewater treatment plant is also releasing water and recharging the aquifer a couple of miles upstream from this flowing stretch in the Charleston area. Ian James,, 7 Sep. 2021 The Southerly Wastewater Treatment Plant located north of the Interstate 480 bridges discharges into the Cuyahoga about 10 miles upstream from the lake. Peter Krouse, cleveland, 20 Aug. 2021

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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Time Traveler for upstream

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The first known use of upstream was in 1681

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Last Updated

7 Nov 2021

Cite this Entry

“Upstream.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2021.

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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.


adverb or adjective
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 — 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

More from Merriam-Webster on upstream

Nglish: Translation of upstream for Spanish Speakers


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