Definition
To determine whether something will be successful or a failure; to have a decisive impact on something.
This product launch is make-or-break for the company's future; it could either make the company a household name or lead to its downfall.
His upcoming audition is make-or-break for his dream of becoming an actor; it will determine whether he has a career in show business.
This game is make-or-break for their chances of advancing to the finals; it will determine whether they move on or not.