From Longman Dictionary of Contemporary Englishroot beerˈroot beer noun [countable, uncountable] DFDa sweet brown non-alcoholic drink made from the roots of some plants, drunk especially in the US
Examples from the Corpus
root beer• Alice Hawthorne sold ice cream cones and root beer floats to the people of Albany, Ga.• Then pause for a cold root beer in a turn-of-the-century saloon.• This week I got root beer.• She dropped ice cubes into a glass and poured in root beer.• After the 30-minute play, the audience is invited to meet the cast over root beer floats.• He said his uncle kept him too busy with the root beer concession. 