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Synonym:  Secondary wave (s-wave) = Shear  Shear wave 

A body wave caused by oscillation of a shear stress in a matter and as such resulting in strain oscillations perpendicular to the direction of s-wave propagation.

In terms of corpuscular structure of the matter the s-wave is characterised by the fact that particles of the matter are moving back and forth perpendicular to the s-wave travel direction (see Fig. 1). 

S-wave can propagate through solids only and move slower than p-wave.

See also

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Physics / Mechanics / Continuum mechanics / Mechanical waves / Body wave

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