angle of repose

1

physics : the angle that the plane of contact between two bodies makes with the horizontal when the upper body is just on the point of sliding : the angle whose tangent is the coefficient of friction between the two bodies

2

or angle of rest : the angle of maximum slope at which a heap of any loose solid material (as earth) will stand without sliding compare angle of slide

Word History

First Known Use

1807, in the meaning defined at sense 1

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