The Collaborative International Dictionary of English v.0.48:

Collision \Col*li"sion\, n. [L. collisio, fr. collidere. See
   Collide.]
   1. The act of striking together; a striking together, as of
      two hard bodies; a violent meeting, as of railroad trains;
      a clashing.
      [1913 Webster]

   2. A state of opposition; antagonism; interference.
      [1913 Webster]

            The collision of contrary false principles. --Bp.
                                                  Warburton.
      [1913 Webster]

            Sensitive to the most trifling collisions. --W.
                                                  Irving.

   Syn: Conflict; clashing; encounter; opposition.
        [1913 Webster]

WordNet (r) 3.0 (2006):

collision
    n 1: (physics) a brief event in which two or more bodies come
         together; "the collision of the particles resulted in an
         exchange of energy and a change of direction" [syn:
         collision, hit]
    2: an accident resulting from violent impact of a moving object;
       "three passengers were killed in the collision"; "the
       collision of the two ships resulted in a serious oil spill"
    3: a conflict of opposed ideas or attitudes or goals; "a
       collision of interests"

The Free On-line Dictionary of Computing (19 January 2023):

collision

   1.  When two hosts transmit on a network at
   once causing their packets to corrupt each other.

   See collision detection.

   2.  hash collision.

   (1995-01-06)