What does "apologue" mean?

Apologue: A story or relation of fictitious events, intended to convey some moral truth; a moral fable. Note: An apologue differs from a parable in this;: the parable is drawn from events which take place among mankind, and therefore requires probability in the narrative; the apologue is founded on supposed actions of brutes or inanimate things, and therefore is not limited by strict rules of probability. Æsop's fables are good examples of apologues.