Definition & Meaning of "what in the world"in English

What is the origin of the exclamation "what in the world" and how is it used?

What in the world is an exclamation used to express shock, disbelief, or confusion about a situation. It appeared in English in the 18th–19th century as a polite alternative to more forceful expressions involving God or strong curses. People used it in everyday speech, literature, and formal writing to react to surprising or confusing events without offending anyone. Today it is inoffensive, widely understood, and neutral, often signaling astonishment, bewilderment, or mild incredulity in both casual and formal contexts.