Originally: designating a group of African languages corresponding approximately to the Bantu subdivision of Niger–Congo languages. In later use…

spec. Designating or relating to a group of African languages forming a subfamily of the Nilo-Saharan phylum and spoken by some East African…

Of, relating to, or designating an African people of south-eastern Sudan and Ethiopia (see sense B. 1) or their Nilotic language (see sense B. 2).