Sheneka has two meanings. The first is "queen of the pure ones". The prefix she- means queen of and neka means pure ones. As slaves converted to Chrisianity and people began to believe more and more that Christ was black, Sheneka became the black version of Mary as in the Virgin Mary. The second meaning is "Supreme woman". Both meanings are derived from two African languages. I van't recall where they are from, but the second meaning was partially discussed in a book about the first experiences of colonialism and slavery in Africa.