the world > matter > constitution of matter > density or solidity > state of being thick enough to retain form > [noun] > process or fact of becoming stiff or hard (3)
stiffness1639
Rigidity, inflexibility; viscosity (of liquids and semi-liquids); density, heaviness, compactness (of soil). Also figurative.
setting1791
The process or fact of becoming set, hard, or stiff; coagulation.
set1837
The action of setting or hardening, or the condition of being set. to take a set: to set.