Definition & Meaning of "great guns"in English

What is the origin of the exclamation "great guns" and how is it used?

Great guns is an exclamation used to express excitement or amazement. It appeared in British English in the 18th century, originally as a nautical term referring to the largest cannons on a ship, and later adopted figuratively as a way to emphasize strong emotion. People used it in everyday speech, literature, and theatrical dialogue to convey surprise, enthusiasm, or admiration. Today it sounds old-fashioned, vivid, and inoffensive, often adding a colorful, energetic tone to expressions of astonishment or excitement.