Basà language is classified as belonging to Kainji family under the sub-phylum Western-Kainji (Croizier and Blench, 1992). It is spoken in North Central Nigeria, that is, all the Federal Councils, Niger, Nasarawa, Benue and Kogi states. This study investigates headedness and the structure of Basà compounds. Data gathering for this work involved interview, the native intuition of the researcher, careful observation of native speakers with a special focus on compounds. Morphologically complex words are headed in language. Williams (1981) proposes the right-headed rule (RHR). The rule was found inadequate and was latter modified by Selkirk (1982). This rule does not account for Basà compounds. Hence, the study attempts to answer the question “which member of the morphologically
complex word heads compounds in Basà?” The investigation focuses on Basà nominal compounds, synthetic compounds and those derived by desententialization. Each category but, one of these complex words is assigned a head. The work discovered that in Basà language, compound words are headed by the left-hand member (N1), but for those compounds that are desententialized, though they are nouns from the syntactic tests carried out in the study, no visible member of the complex words heads them. It disproves the proposal of Williams (RHR) which claims to be universal, because it does not account for Basà language which obeys the left-hand head rule (LHR). The work contributes to the greater understanding of headedness, the complexity of compound structures and the type of
transformation involved especially, desentetialization. Similar studies can be replicated in languages that are syntactically similar, and the findings in the work can stimulate further investigation.
Keywords: Basà language, desententialization, headedness, nominal compounds, percolation and prefixes