Compulsive hoarding (or pathological hoarding) is the acquisition of, and failure to use or discard, such a large number of seemingly useless possessions that it causes significant clutter and impairment to basic living activities such as mobility, cooking, cleaning, showering or sleeping. A person who engages in compulsive hoarding is commonly said to be a "pack rat", in reference to that animal's apparent fondness for material objects.
It is not clear whether compulsive hoarding is a condition in itself, or simply a symptom of other related conditions. Several studies have reported a correlation between hoarding and the presence and/or severity ofobsessive-compulsive disorder (OCD). Hoarding behaviour is also related to obsessive-compulsive personality disorder (OCPD). Hoarding unnecessary possessions may be referred to as syllogomania or disposophobia..." More