What is "overspilling"

Usage examples of "overspilling".

Rising from this, like a massif, was Bowlott’s desk, seemingly the inspiration and model for the whole room, with its own miniature central plain surrounded by overspilling disorder.

Tremors of fear flowed through her in plentiful rillets that repeatedly backed up into an overspilling twitch, jerking her head, her entire body, with the force he'd seen translated through the covers.