a fat, old person, usually in their middle to late sixties. They tend to look much older then they actually are and typically have less than ten years to live. Often times, they can be seen on the beach wearing a speedo, but generally wherever they are they dress as if they are young people.
Unlike an old bag old baggison is not gender specific.
Person one: I saw some old baggisons on the beach today. They male baggison was wearing a speedo and his old baggison wife had a thong. I wanted to gouge my eyes out my eyes with a rusty spoon.
Person two: I saw an old baggison with a miniskirt. She bent over in front of me in Walmart and I went home and cried.