1. An act of colliding; a crash.
2. A condition of opposition or conflict between two or more people or things: the collision between management and labor.
3. Physics A brief dynamic event consisting of the close approach of two or more particles, such as atoms, resulting in an abrupt change of momentum or exchange of energy.
[Middle English, from Late Latin collīsiō, collīsiōn-, from Latin collīsus, past participle of collīdere, to collide; see COLLIDE.]
Synonyms: collision, crash1, impact
These nouns denote violent forcible contact between two or more things: the midair collision of two planes; a crash involving two cars; a crater produced by the comet's impact.
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