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

State officials say the Newsom administration’s ongoing efforts to help salmon populations recover include restoring tidal habitats, modernizing infrastructure, removing barriers that hinder fish migration and reintroducing salmon in traditional spawning areas upstream from dams. —Ian James, Los Angeles Times, 16 Apr. 2025

Along with other advocacy groups and Native American tribes, Greenpeace opposed plans for the pipeline to cross the Missouri River upstream of the Standing Rock Sioux Tribe’s reservation. —Jennifer Safstrom, The Conversation, 11 Mar. 2025

The body of the youngest daughter Sue, 11, was discovered in the river near Camas, Washington, around five months after the family went missing, per the AP, before 13-year-old Virginia's body was found the following day approximately 25 miles upstream from where Sue's remains were discovered. —Becca Longmire, People.com, 7 Mar. 2025

At the Fundy Discovery Site, tourists can witness a tidal bore, or a wave that moves upstream in a river. —Melanie Stetson Freeman, The Christian Science Monitor, 28 Feb. 2025

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