free oscillation

synonym: free sinusoidal oscillation
https://doi.org/10.1351/goldbook.12770
Oscillatory deformation of a material specimen with the motion generated without the continuous application of an external force.
Note: For any real sample of material, the resulting oscillatory deformation is one of decaying amplitudes.
Source:
PAC, 2013, 85, 1017. (Glossary of terms relating to thermal and thermomechanical properties of polymers (IUPAC Recommendations 2013)) on page 1028 [Terms] [Paper]