river

(a view of the Arkansas river, as seen from the pedestrian bridge at Murray Lock & Dam)

"The process of a living language is like the motion of a broad river which flows with a slow, silent, irresistible current." - Noah Webster

Our river comes from Old French rivere, also meaning "river." The Old French rivere can be traced back to Latin ripa, meaning "river-bank." I find it interesting that, etymologically speaking, the word emphasizes the banks of a river rather than the water flowing through the banks' channel. (The Latin word for "river" itself is flumen, and we can see the stem for "flow" in it.)

English has an adjective which can also be traced back to ripa: riparian, meaning "pertaining to river-banks." And the French Riviera is so called because the sea-shore can be referred to as one "bank" of the ocean.

sources: AHD and OED