(Noun) Psychiatry. A unique combination of traits resulting in a personality typified by sociopathic tendencies, a nearly complete unfamiliarity with moral responsibility and social conscience, a proclivity towards lies and thievery, and a near total inability to concentrate sufficiently on any single task resulting in consistenly shoddy workmanship.
This condition is so rare it is only known to exist in one individual, for whom the disease is named.
Sure signs of encountering this individual may include large quantities of bondo, claims of being "handy capped", references to "treats" (meaning "threats"), and unusually frequent references to something called a "shreff" (which is to this date unknown). Infrequently, there may be an air-cooled Volkswagen involved - although this will usually end up being stolen goods.
The victim also suffers from an extreme delusional state (i.e. his wife is hot, he is a top restorer, etc.).
Persons coming in contact with a mariopath would be advised to keep a sharp eye on their wallets.
"That guy is such a complete mariopath, he needs to be put to sleep."