what does "something can wait" mean? is it common to say?

Native speaker’s answer
Rebecca
You can take "[something] can wait" for its literal meaning! It's an informal expression commonly used when you want to say that something isn't urgent or your most important priority, so you can do it/pay attention to it later. Ex: Your job can wait, but your health can't. Ex: Dinner can wait. This basketball match on tv is way more important.