Definitions for one-up
Random House Webster's College Dictionary
having gained an advantage, esp. over a rival.
Origin of one up:
to gain an advantage over; be a move, step, etc., ahead of:
to one-up the competition.
Category: Common Vocabulary
Origin of one-up:
An additional life or an object that increases the player's number of chances or "lives" by one.
If you hit that block, you can get a one-up.
To outdo, to do something slightly better than a competitor's prior effort.
Every year the neighbors try to one-up each other with their holiday lights.