δραστήριον

From LSJ

τούτων γάρ ἑκάτερον κοινῷ ὀνόματι προσαγορεύεται ζῷον, καί ὁ λόγος δέ τῆς οὐσίας ὁ αὐτός → and these are univocally so named, inasmuch as not only the name, but also the definition, is the same in both cases (Aristotle, Categoriae 1a8-10)

Source

Russian (Dvoretsky)

δραστήριον: τό деятельный характер, предприимчивость, решительность Thuc., Plut.