Didactic
Didactic , adjective
[Greek {not transcribed}, from {not transcribed} to teach; akin to Latin docere to teach: compare French didactique. See Docile.]
1.
Fitted or intended to teach; conveying instruction; preceptive; instructive; teaching some moral lesson; as, didactic essays.
Didactical writings.
The finest didactic poem in any language.
2.
excessively prone to instruct, even those who do not wish to be instructed; -- of people. [Pejorative]
Also: Didactical
Didactic , noun
A treatise on teaching or education. [Obsolete] — Milton