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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.]

col·li′sion·al adj.
col·li′sion·al·ly adv.
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.


in the manner of a collision or collisions
References in periodicals archive ?
Source conditions were as follows: Curtain Gas, 40; gas 1, 35; gas 2, 30; temperature, 600; collisionally activated dissociation gas, 12; ion spray voltage, 5500; and entrance potential, 10.
1); the most abundant of these ions were isolated and their collisionally induced dissociation (CID) product ions spectra were obtained.
The following parameters were used: nebulizer gas, 13 L/min; curtain gas, 12 L/min; ion spray voltage, -4,500 V; desolvation temperature, 450[degrees]C; collisionally activated dissociation gas, 8 L/min; declustering potential, -12 V; focusing potential, -180 V; entrance potential, -8 V; collision energy, -45 V; and collision cell exit potential, -51 V.