An exceptionally unclean individual known to posess a pungent aroma similar to the combined smell of baked ham and egg salad. They perform no function in society but yet feel a strong sense of entitlement. In most cases(not all) your typical dirty marvin has grown so fat they have lost the ability to wipe their own ass thus contributing to the smell. A dirty marvin can be a male or female of any race, as long as they meet the criteria mentioned above.
While at Walmarts today you wouldnt believe how many dirty marvins I saw. Must've been benefits day!