Entry 1 sense Webster, 1913 Binarseniate · Bin·ar·se·ni·ate · IPA /ˌbaɪnɑː(ɹ)ˈsiːnieɪt/ 01 n. A salt having two equivalents of arsenic acid to one of the base. 1. A salt having two equivalents of arsenic acid to one of the base.(Chem.)