Definition of river running in US English:

river running

noun

  • The action of navigating a river, (now) especially the leisure activity of navigating a fast-flowing river in a small craft (as a raft or canoe).

Origin

Early 20th century; earliest use found in Bulletin. From river + running.

Pronunciation

river running

/ˈrɪvə ˌrʌnɪŋ/