The phrase "The shot heard round the world" refers to the gunfire that marked the beginning of the Battles of Lexington and Concord on April 19, 1775.

This moment symbolized the start of the American Revolutionary War and resonated far beyond the colonies, representing the struggle for freedom and self-determination. It encapsulated the idea that the conflict would have global implications, inspiring movements for liberty and independence in other nations. The phrase emphasizes the historical significance of these battles as a catalyst for change and the fight against oppression.