Stiffening

Part of speech: noun, verb

Definitions

1. The action of causing an object to become less pliable or more solid, often enhancing its durability and resistance to deformation
2. The process of increasing the firmness or rigidity of a material or structure
3. An act that results in a material becoming less flexible and more robust

Etymology: "Stiffening" is the present participle and gerund of "stiffen", which in turn comes from Middle English "stifnen". That verb was built from the adjective "stiff" and the suffix "-en", which turns an adjective into a verb meaning to make or become that quality, as in "widen", "harden" or "soften". So the word's core sense is simply "to make stiff," and its use for things that grow firmer or more rigid, from starched collars to hardening paste, follows directly from that.

Synonyms: hardening, firming, tensing, rigidifying, solidifying

Antonyms: softening, relaxation, loosening, diminishing, yielding