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

This last effort to mitigate flooding will affect dozens of communities both upstream and downstream in the Menomonee River watershed for the better, according to Schindler. —Bridget Fogarty, Journal Sentinel, 5 Nov. 2024

Klamath Chairman William Ray said his tribe had fished the last salmon out of the river in the early 20th century after the first of the dams, Copco I, stopped fish from coming upstream to spawn. —Debra Utacia Krol, USA TODAY, 5 Nov. 2024

Although Upper Klamath Lake was known for unusually huge rainbow trout, some two feet long, that attracted anglers in droves, little thought was given to the Chinook salmon that had once thrived in the Klamath River but were no longer seen so far upstream. —Dan Walters, The Mercury News, 5 Nov. 2024

The slide created new rapids at the entry point, with sediment and mud continuing to shift, altering river conditions along a three-mile stretch upstream. —Tom Howarth follow, Newsweek, 4 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