word-forming element used in English from c. 1300 and meaning "against, in opposition; in return; corresponding," from Anglo-French countre-, French contre-, from Latin contra "opposite, contrary to, against, in return," also used as a prefix (see contra (prep., adv.)). A doublet of contra-. In some cases it probably represents a purely English use of counter (adv.).
late 14c., curraunt, "that which runs or flows," from Old French corant (Modern French courant), from Old French corant (see current (adj.)). Meaning "a flowing," especially "portion of a large body of water or air moving in a certain direction," is from 1550s. Applied from 1747 to the flowing of electrical force through a conducting body (electricity formerly was regarded as a sort of fluid).
<a href="https://www.etymonline.com/word/counter-current">Etymology of counter-current by etymonline</a>
Harper, D. (n.d.). Etymology of counter-current. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/counter-current