In a direction or manner that is opposite to the main current or flow; in the opposite direction to what is expected or established.
From countercurrent + -wise (suffix meaning direction or manner). The -wise suffix comes from Old English wīse (way or manner). This rare compound emphasizes the directional aspect of opposing a current or trend.
This is an archaic or highly technical word that combines maritime and directional language—you'd see it in old nautical texts or physics papers, and it shows how English speakers created super-specific words to describe going in exactly the opposite direction.
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