Euclid Book 2 Definitions
Statement
Any rectangular parallelogram is said to be contained by the two straight lines containing the right angle.
Original statement
πᾶν παραλληλόγραμμον ὀρθογώνιον πϵριέχϵσθαι λέγϵται ὑπὸ δύο τῶν τὴν ὀρθὴν γωνίαν πϵριϵχουσῶν ϵὐθϵιῶν.
Statement
In any parallelogrammic area let any one whatever of the parallelograms about its diameter with the two complements be called a gnomon.
Original statement
παντὸς δὲ παραλληλογράμμου χωρίου τῶν πϵρὶ τὴν διάμϵτρον αὐτοῦ παραλληλογράμμων ἓν ὁποιονοῦν σὺν τοῖς δυσὶ παραπληρώμασι γνώμων καλϵίσθω.