| the external force acting on an object or surface parallel to the slope or plane in which it lies; the stress tending to produce shear. |
| shear stress
A form of stress that subjects an object to which force is applied to skew, tending to cause shear strain. For example, shear stress on a block of wood would arise by fixing one end and applying force to this other; this would tend to change the block's shape from a rectangle to a parallelogram. See also strain. |