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(physics) The level of stress at which a solid undergoes a greater change in strain than predicted by Hooke's law; often followed by necking and breaking.

Stress–strain curve showing typical yield behavior for nonferrous alloys (stress,  ${\displaystyle \sigma }$, shown as a function of strain,  ${\displaystyle \epsilon }$):

1. True elastic limit
2. Proportionality limit
3. Elastic limit
4. Offset yield strength