
thumb|right|Extension of a coil spring, \delta, caused by an axial force, F.
thumb|right|Extension of a coil spring, \delta, caused by an axial force, F.
Stiffness or rigidity is the extent to which an object resists deformation in response to an applied force. The inverse of stiffness is flexibility or pliability: the more flexible an object is, the less stiff it is. Other terms with related meanings are compliance and elasticity.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).