1. continue something in an even more determined, focused way than before
double down on your efforts
To 'double down' in gambling, means to double a bet. If someone 'doubles down' they put in twice as much effort or renew their commitment to a particular goal or cause, usually one that has a risk associated. Although this expression is often used with regards to discussing effort, commitment, and determination, it does not always have positive connotations. Doubling down on something can be a sign of rudeness or stubbornness, especially if you have said something objectively offensive, or are doing something that is destructive or ineffective.