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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


of or relating to a collision or collisions
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
"A similar quandary is likely to become more prominent and collisional between the S-400 missiles versus the F-35 fighter jets." Ankara may be pushed to reluctantly keep the ball rolling for a little while longer with Moscow, at least until it comes up with a creative solution to its economic problems, according to Has.
Because of this limitation, DNS studies simulating individual cloud particles have focused on the impacts of small-scale turbulence on diffusional and collisional growth of cloud droplets [see the review of Grabowski and Wang (2013)].
The orogenic gold deposit is the typical manifestation in the Zagros collisional Orogenic belt (Aliyari et al., 2009; Alizadeh-Dinabad et al., 2013; Almasi et al., 2015; Almasi et al., 2017).
The observed differences in the metamorphic grade is supported by their occurrence in the field; amphibolites are restricted to the south while garnet amphibolites and eclogites to the north of the valley which is consistent with the increasing grade of metamorphism towards the collisional boundary (MMT).
Galewsky, J" and Sliter, W., 1997, Measurement of tectonic surface uplift rate in a young collisional mountain belt: Nature, v.
The study, titled "The X-Ray Luminosity Function of Ultra Luminous X-Ray Sources in Collisional Ring Galaxies," was recently published in ( the Astrophysical Journal.
"This is probably a sign that the object itself was not a collisional fragment.
For the ease of comparison with results from the literature, the plasma under consideration is inhomogeneous, cold, unmagnetized, and collisional. The plasma is also assumed to be confined to a cylindrical structure and under illumination from a transverse magnetic (TM) plane electromagnetic wave with electric field parallel to the cylinder's axis and in a situation of normal incidence, as shown in Figure 1.
Kochanov, "Effect of diffraction of molecules on collisional line narrowing," Optics and Spectroscopy, vol.
As so, Montasser tackled the collisional relation between art and religion in three articles this week, from a historical perspective all the way up to extremist approaches.
(15) The preliminary study was based on plasma kinetics and made use of a quasi-linear approximation to the collisional Liouville equation to derive the distribution function, F (r, v), of brain activities in the neural phase space (i.e., 3D position space r and 3D velocity space v).
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