Used to describe an overly cautious teenage boy who spends a large majority of his time talking to others instead of doing what he is supposed to. Generally takes up a lot of time doing absolutely nothing.
Guy: Damn, Jackson is being really slow.
Girl: Yeah, he's such a Grandma.
A little old woman depicted in cartoons as a hunchbacked russian with wrinkly skin and white hair up in a bun with remarkably tiny glasses and complains to his husband about every damn thing, often bakes cookies.