one-upsmanship

noun

1. the art or practice of achieving, demonstrating, or assuming superiority in one’s rivalry with a friend or opponent by obtaining privilege, status, status symbols, etc.: the one-upmanship of getting into the president’s car pool.

noun

1. informal the art or practice of achieving or maintaining an advantage over others, often by slightly unscrupulous means

n.1952, from noun phrase one up “scoring one more point than one’s opponent” (1919).