تعریف و معنای "[have] (bigger|better|other) fish to (fry|catch)"

What is the origin of the idiom "have bigger fish to fry" and when to use it?

The idiom "have bigger fish to fry" likely has its origins in fishing and hunting activities where individuals prioritize catching or cooking the most valuable or desirable fish or game. When used figuratively, it means that a person has more important or pressing matters to attend to than the one currently under discussion, often dismissing it as less significant.