collision

n. crash, colliding of two or more objects

In physics, collision means the action of bodies striking or coming together (touching).
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Collision Obstetrics A mechanical obstruction to the birth of twins, such that the lay of one fetus impedes the engagement of the other; the most [more]Collision - Community and Resources

Noun
1. (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"
(synonym) hit
(hypernym) contact, impinging, striking
(derivation) collide, clash
(classification) physics, physical science, natural philosophy
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"
(hypernym) accident
(hyponym) fender-bender
(derivation) collide, clash
3. a conflict of opposed ideas or attitudes or goals; "a collision of interests"
(hypernym) dispute, difference, difference of opinion, conflict
(derivation) clash, jar, collide

n. collision, hit, clash; shock, smash