agua fresca
noun
agua fres·ca ˈä-gwə-ˈfre-skə 
plural aguas frescas
: a beverage consisting of water and sugar with fruits, grains, or seeds added for flavoring
For a rancho-style summer barbecue, we make a big glass barrel of agua fresca, and sometimes it's more popular than the beer or wine if the day is particularly hot.
Jacqueline Higuera McMahan, California Rancho Cooking, 2001
Jacqueline Higuera McMahan, California Rancho Cooking, 2001
Word History
Etymology
borrowed from American Spanish, literally, "fresh water"
First Known Use
1962, in the meaning defined above