"act of striking or dashing together," early 15c., from Late Latin collisionem (nominative collisio) "a dashing together," noun of action from past-participle stem of Latin collidere "to strike together" (see collide).
the collision of the particles resulted in an exchange of energy and a change of direction
the collision of the two ships resulted in a serious oil spill
three passengers were killed in the collision
a collision of interests