FTP, identify this aspect of special relativity that suggests the contraction of a moving body in the direction of its motion.
It was proposed independently by its two co-discoverers to account for the null result of the Michelson-Morley experiment.  Generally regarded as negligible in real world systems, the original hypothesis proposing it regarded it as a real one accompanying the absolute motion of the body.  It states that the length of a moving body in an alternate frame of reference equals the square root of one minus the velocity squared divided by the speed of light squared.  FTP, identify this aspect of special relativity that suggests the contraction of a moving body in the direction of its motion.
It was proposed independently by its two co-discoverers to account for the null result of the Michelson-Morley experiment.  
Lorentz-Fitzgerald contraction (accept either name)