What is the definition of wadi

Wadi, alternatively wād, North African Arabic Oued, is the Arabic term traditionally referring to a valley. In some instances, it may refer to a dry riverbed that contains water only when heavy rain occurs. Patrons: GoogIe

It's Arabic term to dry valley that will contain water if it rains. It's a beautiful landscape that have golden sands, blue clear water, warm temperature, silver clouds sailing, sky blue sky, it's a part of a desert that contains colors of life. It's a dry waterbed, but dangerous because rocks underneath the ground can kill you.

answer; specialization of production;

sorghum farming likely spread with the bantu migration. there is your answer i had to get it wrong to get this right so i hope ya'll enjoy!