Rigid body

In physics, a rigid body is an idealization of a solid body in which deformation is neglected. In other words, the distance between any two given points of a rigid body remains constant in time regardless of external forces exerted on it.

Quotes

 * Rigid bodies can be divided into two types: unconstrained rigid bodies, such as the pieces from a breaking up fighter plane in Pearl Harbor, and rigid bodies connected by joints which constrain their degrees of freedom (known as articulated rigid bodies), such as the battle droids in Star Wars: Episode I or Davy Jones’ beard in Pirates of the Caribbean: Dead Man's Chest.
 * A. McAdams, S. Osher and J. Teran, “Crashing Waves, Awesome Explosions, Turbulent Smoke and Beyond: Applied Mathematics and Scientific Computing in the Visual Effects Industry.”, Notices of the AMS, 2010; 57 (5): 614-623.