a dog-eat-dog world

A society, situation, industry, etc. characterized by ruthless behavior and competition. It's a dog-eat-dog world for students today. Everyone is competing nonstop for awards and recognition. Your summer job at your uncle's company is pretty cushy, but don't expect every job to be that way—it's a dog-eat-dog world out there. There are so few houses on the market right now that real estate is truly a dog-eat-dog world.