IPA: /ˈdaʊnˌrɪvər/
KK: /ˈdaʊnˌrɪvər/
In the direction of the flow of a river, towards where the river ends or meets another body of water.
The boat drifted downriver, enjoying the gentle current.
In the direction of the flow of a river, toward the place where the river meets a larger body of water.
The boat floated downriver, enjoying the gentle current.
Downriver → It is formed from "down" (from Old English "dūne", meaning downward or lower) and "river" (from Latin "rivus", meaning stream or brook). The word "downriver" refers to the direction that is lower or downstream along a river.
Think of going 'down' ('dūne') the 'river' ('rivus') — that's why downriver means moving in the direction of the flow of the river.