Source : WordNet®

isometry
     n 1: the growth rates in different parts of a growing organism
          are the same
     2: a one-to-one mapping of one metric space into another metric
        space that preserves the distances between each pair of
        points; "the isometries of the cube"
     3: equality of elevation above sea level
     4: equality of measure (e.g., equality of height above sea
        level or equality of loudness etc.)

Source : Free On-Line Dictionary of Computing

isometry
     
         A {mapping} of a {metric space} onto another or
        onto itself so that the distance between any two points in the
        original space is the same as the distance between their
        images in the second space.  For example, any combination of
        rotation and translation is an isometry of the plane.
     
        (1997-12-13)