One who lacks in mental capacity; often this problem is supplemented by a psychiatric problem in which the subject does not understand what is going on around him - much like a dissociative disorder, however, when someone is said to be an Ellis, generally the focus of the comment is on the sheer stupidity of an action or phrase that has been put forward. Those who are prone to being an 'Ellis'(Also known, in context, as "Pulling an Ellis") often also misuse the trust put in them by close relatives or friends, due to the person in question having no ability to realise that the people he is attempting to mislead, in fact fully understand that the Ellis in question's words have little or no credibility, as they are almost always lies. This situation is not helped by an Ellis's tendancy to tell outrageous lies that no sane person would believe; The inability of the subject to understand that their lies are outrageous never leaves them and is a very large hindrance in later life.
This is truly a terrible affliction on humanity, those who fall in the Ellis category of mental state often show prominent signs of rapid brain matter deterioration, resulting in a decreased overall intelligence. Ellis's are kept in dark, damp rooms and fed high protein Tofu meals to slow the deterioration of the brain. Strong light can cause the subject to completely "flip out", often resulting in a rampage of idiocy in the immediate vicinity.
There is no cure for the Ellis affliction, however you can rest safe in the knowledge that you must be born with this disease; it cannot be passed on, even through blood transfer. This is an extremely rare disease, with just one serious case known to exist to this day.
The Ellis rate of Perth, Western Australia is about 1 in 2,000,000.