Young's Modulus

The linear-elastic material constant E equal to the ratio of uniaxial (axial) engineering stress to axial engineering strain within the material's elastic range (σ = E·ε); units: pascal (Pa).

A material property defined as the ratio of uniaxial tensile (or compressive) engineering stress to engineering strain within the linear elastic region of the stress–strain curve; numerically E = σ/ε for small strains, with SI units pascal (Pa).

Elastic stiffness parameter defined as the ratio of uniaxial tensile (or compressive) stress to the corresponding axial strain within the linear elastic (proportional) region of a material's stress–strain response; units of pressure (Pa).