softener
This term refers to a functional agent designed to alter the physical properties of a material or liquid. In the context of laundry, it specifically targets the tactile quality of textiles, often leaving a chemical residue to reduce friction and static.
When applied to water, the term describes a chemical process of ion exchange or sequestration to eliminate mineral hardness. Because the word describes a specific tool or substance, it is used concretely in domestic and industrial settings. It is distinct from "softening," which describes the process itself, whereas "softener" identifies the agent or device responsible for that change.
Meanings
A substance added to laundry during the rinse cycle to make fabrics feel smoother and reduce static electricity.
She adds a capful of fabric softener to every load of towels.