Pronunciation: (up'strēm'), [key]
toward or in the higher part of a stream; against the current.
1. directed upstream; situated upstream: an upstream journey; an upstream hideout.
2. Com.of or pertaining to the early stages in the operations of a business or industry, as exploration and production in the oil business (opposed to downstream).
3. against or opposite to the direction of transcription, translation, or synthesis of a DNA, RNA, or protein molecule.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.