Translate upstream | into French | into German | into Italian | into Spanish Definition of upstream
adverb & adjective
moving or situated in the opposite direction from that in which a stream or river flows; nearer to the source: [as adverb]:a salmon swimming upstream [as adjective]:the upstream stretch of the Platte Biology situated in or toward the part of a sequence of genetic material where transcription takes place earlier than at a given point. at a stage in the process of gas or oil extraction and production before the raw material is ready for refining.