Upstream  In Stream Adverb Direction Adjective Opposite Position

Merriam-Webster's Collegiate Dictionary

 DATE  1681

upstream
  1681, from up- + stream. In common use from c.1890.

upstream
up·stream / 7Qp5stri:m / (also less frequent up·river) adverb    ~ (of / from sth) along a river, in the opposite direction to the way in which the water flows
   向(或在)上游；逆流:
   The nearest town is about two miles upstream. 
   最近的城镇大约在沿河向上十英里处。 
   upstream of / from the bridge 
   在桥的上游 
   OPP  

downstream

upstream
I. \ˈ ̷ ̷| ̷ ̷\ adverb
Etymology: up (IV) + stream, n.
: in a direction nearer the source of a stream
 < traveled upstream >
 < an extensive tract a few miles upstream — American Guide Series: Louisiana >
II. adjective
1. : directed upstream
 < an upstream course >
2. : situated or occurring upstream
 < the upstream countries — F.W.Morgan >
III. adverb
1. : in or to a position within the production stream closer to manufacturing processes
2. : 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 hydroxyl group attached to the position labeled 5′ in the terminal nucleotide 
 < a nucleotide sequence located upstream of the initiation codon >
— compare  herein
IV. adjective
: of or relating to a portion of the production stream closer to basic extractive or manufacturing processes 
 < an upstream chemical manufacturer >
 < upstream profits >