Collins COBUILD Advanced Learner's English Dictionary - cracking

1. You use cracking to describe something you think is very good or exciting. (BRIT INFORMAL) It’s a cracking novel... = great, brilliant ADJ: usu ADJ n 2. If you tell someone to get cracking, you are telling them to start doing something immediately. (BRIT INFORMAL) Mark, you’d better get cracking, the sooner the better... PHRASE: get inflects