lathery

Lathery refers to the quality of producing or being covered in lather. Lather is a foam or froth formed when soap or detergent is mixed with water and agitated. This frothy substance is often a desirable characteristic in cleaning products, as it is associated with effective cleansing and lubrication. The ability of a product to generate abundant lather is frequently highlighted in marketing.

The formation of lather involves the interaction of surfactants, which are molecules with both water-attracting (hydrophilic) and water-repelling (hydrophobic) parts. When mixed with water, these molecules arrange themselves to reduce surface tension, trapping air and forming bubbles that create the lather. The specific properties of the surfactants, the water hardness, and the degree of agitation all influence the volume, stability, and texture of the lather produced.

In many contexts, a thick, rich lather is perceived as a sign of a product's strength and efficacy. This is particularly true for soaps used for washing the body or hands, as well as for shaving creams, where lather helps to soften facial hair and provide a smooth surface for the razor. While the visual appeal and tactile sensation of lather are often valued, its cleansing power is primarily due to the surfactant action, not the lather itself. Some modern cleaning agents are designed to be low-lathering, which can be advantageous in certain applications, such as in automatic dishwashers or washing machines, where excessive foam can impede performance.