| Noun | 1. | River Kasai - a river of southwestern Africa that rises in central Angola and flows east and then north (forming part of the border between Angola and Congo) and continuing northwest through Congo to empty into the Congo River on the border between Congo and Republic of the CongoAngola, Republic of Angola - a republic in southwestern Africa on the Atlantic Ocean; achieved independence from Portugal in 1975 and was the scene of civil war until 1990 river - a large natural stream of water (larger than a creek); "the river was navigable for 50 miles" | |