1. A snide description of an action or event that lacks legitimacy.
(Legitimacy as pertaining to the feelings of the person issuing the comment)
2. Sharp disapproval of ones actions, affiliations, opinions, beliefs or rhetoric.
The free masons are a jackastic organization.
Denial that CO2 emissions are responsible for global warming is jackasstic.
Harris county is jackassticly overpopulated.
Ex: My old roomate constantly makes jackasstic comments about things he does not know.