Boomer

Short for Boomerang. For example, a kidult failing to make their way in life, thus never able to completely cut the apron strings from mum and dad. Thus returning home to said mum and dad when the latest venture fails and need to return home for some free food and digs. All the while hating on said parents for actually managing their own formative years to provide for themselves and their selfish kids.

Like a boomerang, every time I chuck out his useless ass he returns like a Boomerang, hence the nickname for incompetent late age kids Boomer.