The Great Rift Valley, of East Africa.

(geology) A graben structure between two tectonic plates which are opening relative to each other. / (geology) A mid-oceanic ridge system with central valleys.

plural of rift valley

(geology) The continuous system of rift valleys in the East African Rift.

(medicine) A mosquito-borne, acute, febrile, viral disease of humans and animals, caused by an RNA virus of the genus Phlebovirus, which occurs in northern and eastern Africa.