upstream

adverb or adjective

up·​stream ˈəp-ˈstrēm 

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

From a sourcing management perspective, this stability enables better decisions upstream. —Sophia Chu, Sourcing Journal, 22 Jan. 2026

These current protections cover 225,504 acres in the Superior National Forest and center around the Rainy River Watershed that lies upstream of the BWCA. —Christine Peterson, Outdoor Life, 21 Jan. 2026

Several miles upstream from Eagle Creek, the TriCo Regional Sewer Utility and the Zionsville Wastewater Treatment Plant discharge into streams that feed the reservoir. —Sophie Hartley, IndyStar, 20 Jan. 2026

Over a span of two minutes and 31 seconds, the Aggies assumed command with a 9-2 run — eight from guard Rylan Griffen — and just like that, the Horns were swimming upstream in what must have felt like a thousand-pound weighted vest. —Cedric Golden, Austin American Statesman, 18 Jan. 2026

Word History

First Known Use

1681, in the meaning defined at sense 1

Rhymes for upstream

• abeam
• airstream
• bloodstream
• daydream
• downstream
• esteem
• extreme
• grapheme
• hakim
• hornbeam
• lexeme
• mainstream

Kids Definition

upstream

adverb or adjective

up·​stream ˈəp-ˈstrēm 

: at or toward the beginning of a stream : against the current

salmon swimming upstream

Medical Definition

upstream

adverb or adjective

up·​stream ˈəp-ˈstrēm 

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