di·dac·tic 
(dī-dăktĭk) also di·dac·ti·cal (-tĭ-kəl)
(dī-dăktĭk) also di·dac·ti·cal (-tĭ-kəl)adj.
1. Intended to instruct.
2. Morally instructive.
3. Inclined to teach or moralize excessively.
[Greek didaktikos, skillful in teaching, from didaktos, taught, from didaskein, didak-, to teach, educate.]
di·dacti·cal·ly adv.
di·dacti·cism (-tĭ-sĭz′əm) n.