Ethiopian Semitic (also known as Ethiopian, Ethiosemitic, Ethiopic, or Afro-Semitic) is a language group, which together with Old South Arabian forms the Western branch of the South Semitic languages. The languages are spoken in both Ethiopia and Eritrea, and one of these languages, the Tigre language, is spoken in both Eritrea and Sudan. Some linguists have begun calling this group "Afro-Semitic" to avoid the exclusive focus on Ethiopia, but its use is not widespread.
The division into Northern and Southern branches has been accepted for many years (Cohen 1931, Hetzron 1972), but Voigt has now challenged this.
While focused on Semitic languages as the only branch of the broader Afroasiatic languages that has its distribution outside Africa, a recent study by Kitchen et al. proposed through the use of Bayesian computational phylogenetic techniques that "contemporary Ethiosemitic languages of Africa reflect a single introduction of early Ethiosemitic from southern Arabia approximately 2800 years ago", and that this single introduction of Ethiosemitic underwent "Rapid Diversification" within Ethiopia and Eritrea.
Cohen, Marcel. 1931. Études d’éthiopien méridional. Paris.
Hetzron, Robert. 1972. Ethiopian Semitic: studies in classification. Manchester: Manchester University Press.
Weninger, Stefan. Vom Altäthiopischen zu den neuäthiopischen Sprachen. Language Typology and Language Universals. Edited by Martin Haspelmath, Ekkehard König, Wulf Oesterreicher, Wolfgang Raible, Vol. 2: 1762-1774. Berlin: Walter de Gruyter.