What does "class" mean here? Is it commonly used?
Native speaker’s answer
Rebecca
When someone says that something is "class," they mean that it is excellent or really good. The speaker has used it to compliment her friend's singing performance. This is slang that is commonly used in the UK. Ex: Wow, did you see that skateboard trick? That was class. Ex: Adele's performance at the Grammys was class.