[noun] (physics) an 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" Synonyms:hit
[noun] 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"
[noun] a conflict of opposed ideas or attitudes or goals; "a collision of interests"