Similar to the "Allspark" in the Transformers franchise which sparks independent life in electronic/mechanical objects upon contact, the Tardspark is a person who acts like a tard and sparks a spontaneous chain-reaction of tard-like behavior in those people around him/her. A person who encourages and/or instigates tard-like behavior in others.
Otherwise peaceful gathering in the movie theater courtyard. Suddenly, tard A starts yelling at and mooning passersby - convinces his friends to do the same. Security guard shows and arrests all. Onlooker shakes head and comments, "the fucking tardspark strikes again."
A tardsack is a dinkus that is so mentally retarded and has such a sack personality, that they fail. This fail is so great, that they may become a tardnugget.
a mentally handicapped person who masturebates in places where he thinks that he cannot be seen by the public, but really, he can. can also be used to insult another person. similar to when one calls another a "retard"