1. do something as fast as possible
go hell for leather to get something done in time
The idiom to go 'hell for leather' means to go out quickly or as fast as possible. To go 'hell for leather' can also mean to give something you're all or to go all in or to do something to the best of your ability with all of your resources. If you go 'hell for leather' or as quickly as possible it can also mean that you are in danger of being careless or reckless.