The Dagbani Dictionary glosses zaabia (plural zaabianima) as 'a gourd rattle', and also 'a person (usually a girl) who shakes a gourd rattle as an accompaniment to the fiddle'. Wilson's 'The Drummer's Path' (1992, p. 39) shows Dagomba musicians playing 'the zaabia rattle and gondze one-string fiddle'.
A zaabia player shook the gourd rattle to accompany the one-string fiddle.