Agua is a Spanish surname meaning "water," originally given to someone who lived near a body of water or whose occupation involved handling water, such as a water carrier or irrigation worker. The name derives from the Latin aqua (water), a root also seen in related surnames like Aguado, which shares the same aqua- stem and was often used to denote a water source or place name. As a topographic surname, Agua is most common in Spain and Spanish-speaking Latin American countries, where it may have arisen independently in multiple regions given the abundant physical landscape features (rivers, lakes, springs) that could have inspired the name.