Return to the home page.

Expand/collapse menu.

Visit Our Sites

Unabridged Dictionary

Learner's Dictionary

Word Central for Kids

Collegiate Dictionary

Expand/collapse menu.

Premium Services

Unabridged Dictionary

Collegiate Dictionary

Encyclopedia Britannica

Institutional Subscriptions

Expand/collapse menu.

Expand/collapse menu.

Word of the Day

Subscriber Help

Expand/collapse menu.

More Word Games

Daily Crosswords

Expand/collapse menu.

Open Dictionary

Alphabetical Browse

Browse Categories

Submit an Entry

Expand/collapse menu.

Spelling Bee Hive

Hive Headquarters

Spelling Champion

Spelling Reform

Expand/collapse menu.

Word for the Wise

Today's Broadcast

Expand/collapse menu.

Books and CD-Roms

Online Services

Palm and Pocket PC

Expand/collapse menu.

Looking Up a Word

Citing the Dictionary

Audio Pronunciations

Word Games Help

Expand/collapse menu.

Merriam-Webster FAQ

Advertising Info

Copyright Notice

Also Visit:
Unabridged
Visual

ESL:
Learner's
for Kids:
Word Central
Spell It!

Browse the Medical Dictionary:: A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z; #

upstream

Main Entry:: up·stream
Pronunciation:: \ˈəp-ˈstrēm\
Function:: adverb or adjective

: 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 <a small coding sequence is located just upstream from each…gene — J. N. Goldman et al>—compare downstream

Learn more about "upstream" and related topics at Britannica.com

Pronunciation Symbols