yield strength

(mechanics) The stress at which a material exhibits a specified deviation from proportionality of stress and strain.

A definite proportionality obtained by drawing a line parallel to the proportional limit line. Yield strength is reported in terms of the degree of strain.

The stress at which a material exhibits a specified limiting deviation from the proportionality of stress to strain.

In mechanics, the stress at the elastic limit of a material's stress-strain curve.