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

Following the water upstream, the villagers discovered the source of the problem: a crumbling bridge sending person after person into the rapids. —Robert Pearl, Forbes, 9 Dec. 2024

In Congress How long will Pete Hegseth make it as the nominee?: Pete Hegseth is swimming upstream to keep his nomination to be President-elect Trump’s Defense secretary alive. —Cate Martel, The Hill, 4 Dec. 2024

By August, all four dams were gone, freeing the river to carry on the work of healing itself, and providing migrating salmon a clear route upstream for the first time in more than a century. —Jeff Moag, Outside Online, 3 Dec. 2024

Despite this positive direction of travel, the salt line could still shoot back upstream quickly if conditions worsen again. —Yaakov Katz, Newsweek, 28 Nov. 2024

Word History

First Known Use

1681, in the meaning defined at sense 1

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