Virtuous, pure from unlawful sexual intercourse, from O.Fr. chaste “morally pure,” from L. castus “pure, chaste.”
Dialectic
Dialectic, also known as the dialectical method, is a discourse between two or more people holding different points of view about a subject but wishing to establish the truth through reasoned argumentation.
Didactic
Intended to teach, particularly in having moral instruction as an ulterior motive.
Dracontia
A precious stone, said to be found in the heads of serpents. Borrowed from Ancient Greek δρακοντίας (drakontías), from δράκων (drákōn, “serpent, dragon”).