Kwadi language
Kwadi  was a "click language" once spoken in the southwest corner of Angola. It went extinct some time around 1960. There were only fifty Kwadi in the 1950s, of whom only 4–5 were competent speakers of the language. Three partial speakers were known in 1965, but in 1981 no speakers could be found. Although Kwadi is poorly attested, there is enough data to show that it is a divergent member of the Khoe family, or perhaps cognate with the Khoe languages in a Khoe–Kwadi family.