What does big mean in slang?

Excuse me, could you please clarify for me what exactly is meant by the term 'big' when used in slang? I've noticed it being used in various contexts and am curious about its specific connotations. Is it simply a reference to size, or does it carry a deeper meaning, such as significance, importance, or perhaps even an element of admiration? I'd appreciate your insights into this commonly used yet potentially multi-faceted slang term.