/ ˈrɪvə(r); NAmE / noun
( abbr. R. ) a natural flow of water that continues in a long line across land to the sea / ocean :
the River Thames
the Hudson River
on the banks of the river (= the ground at the side of a river)
to travel up / down river (= in the opposite direction to / in the same direction as the way in which the river is flowing)
the mouth of the river (= where it enters the sea / ocean)
Can we swim in the river ?
a boat on the river
They have a house on the river (= beside it) .
river (of sth) a large amount of liquid that is flowing in a particular direction :
Rivers of molten lava flowed down the mountain.
see sell verb
Middle English : from Anglo-Norman French , based on Latin riparius , from ripa bank of a river.