stiffer

Stiffer is the comparative form of the adjective stiff. It describes something that resists deformation more than another object under the same load, or something that is more rigid in its structure or behavior. The term is used across science, engineering, and everyday language to indicate greater rigidity or severity.

In materials science and engineering, stiffness refers to a body's resistance to elastic deformation. A stiffer component deflects less under an applied force. For a simple spring, stiffness is quantified by k = F/δ, where F is the force and δ is the resulting displacement. Increasing a material’s Young’s modulus or altering geometry (for example, a larger cross-sectional area) can raise stiffness. Stiffness is related to, but distinct from, strength and hardness; a stiff element may still fail if subjected to excessive force.

In everyday use, stiffer can describe more stringent rules, stricter penalties, or less flexible behavior. For example, a policy becoming stiffer means it imposes more restrictions. In biomechanics and physiology, stiffer tissues or arteries exhibit higher elastic modulus, affecting movement and function.

Etymology-wise, stiffer is formed by adding the comparative suffix -er to stiff. The word is of English origin, with the comparative form following standard patterns for adjectives.