To have a great or excessive abundance of something. The company's had financial difficulties up the yin-yang lately, but the CEO is adamant that it will start making a profit again soon. Sorry, I can't come out tonight, I've got homework up the yin-yang.

To an excessive or extreme degree; in great or excessive abundance. The company's had financial difficulties up the yin-yang lately, but the CEO is adamant that it will start making a profit soon. I only buy video game consoles after they've been out a while and stores aren't charging up the yin-yang for them.