What does "cadmean" mean?

Cadmean: Of or pertaining to Cadmus, a fabulous prince of Thebes, who was said to have introduced into Greece the sixteen simple letters of the alphabet -- Cadmean letters. Cadmean victory, a victory that damages the victors as much as the vanquished; probably referring to the battle in which the soldiers who sprang from the dragon's teeth sown by Cadmus slew each other.