Frothy

Frothy is an adjective used to describe a liquid that is covered with or full of small bubbles or foam on its surface. It is commonly applied to drinks and soaps, but can describe any liquid that has been agitated or carbonated enough to generate foam. The noun froth refers to the foam itself, while the verb froth means to form or become frothy.

The term derives from words for foam in Germanic languages, with the sense extending from the foam-like surface of liquids.

In food and drink, froth characterizes the foam on steamed milk in coffee drinks such as cappuccinos and lattes, as well as the head on beer. In cooking and baking, frothy sauces or batters are light and airy. In industry, froth is central to froth flotation, a process that uses bubbles to separate minerals from ore. Foams and froths are studied in materials science and chemical engineering for their stability and bubble size distribution.

In medicine, frothy sputum can occur with certain pulmonary conditions, and “frothy” is used descriptively in clinical notes.

In literature and everyday language, frothy can describe something light, entertaining, or superficial, as in frothy romance novels or a frothy debate.