What does froth mean?
Froth is a mass of tiny bubbles that forms on or within a liquid, created by agitation, fermentation, or whipping — the white cap on a cappuccino, the spume churned up by breaking waves, or the head on a poured beer. It also functions as a verb: liquids froth when they bubble and foam, whether from boiling, blending, or chemical reaction. Beyond the physical, froth carries a well-established figurative meaning: light, frivolous, or insubstantial talk, writing, or entertainment. A reviewer may dismiss a film as 'mere froth', implying sparkle without depth. The phrase 'froth at the mouth' is widely used figuratively to describe furious, uncontrolled ranting, though it originally described the symptom of rabies. Derived forms include the adjective 'frothy' and the verbs' participles. The word descends from Old Norse, entering English through Scandinavian influence, and it remains a common, everyday term in both British and American usage, valued for its vivid, concrete imagery.
A mass of small white bubbles formed on or in a liquid by agitation, fermentation, or whipping.
"The horse's bridle was flecked with froth after the long gallop."
Also used figuratively for light, trivial content: 'the book is enjoyable froth'.
To form, produce, or cover with froth; to bubble or foam up.
"Beat the egg whites until they froth and hold soft peaks."
Common in the idiom 'froth at the mouth', applied literally to rabid animals and figuratively to rage.
The plural is rare since froth usually describes an uncountable mass of bubbles; it appears mainly when counting distinct instances, such as different froths on sampled drinks.
"The barista compared the froths of three different steamed milks."
An angry dog 'frothing at the mouth' and your morning cappuccino owe their name to the same Old Norse word for sea foam.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of froth
Froth originates in Old Norse, where the related word 'froða' meant foam, and it entered English through the Scandinavian settlement of northern England, likely replacing or absorbing any native Germanic equivalent; it is recorded in English by the medieval period. Its figurative application to trivial or insubstantial matter developed later, extending the image of airy bubbles with no substance. Cognate forms survive in the Scandinavian languages.
Related word forms
How froth is actually used
The figurative sense ('intellectual froth', 'pure froth') carries a dismissive connotation, describing entertainment or writing seen as light and lacking substance. The verb often appears in the fixed phrase 'froth at the mouth', used literally of rabid animals and figuratively of people in a rage. The related adjective 'frothy' likewise spans both literal (frothy beer) and figurative uses (frothy romance).
Easily confused with froth
Foam refers generally to any mass of bubbles (including solid foams like rubber or polystyrene), while froth specifically denotes bubbles on or in a liquid.