noun

• An instance of colliding.
• (physics) Any event in which two or more bodies exert forces on each other in a relatively short time. In a collision, physical contact of two bodies is not necessary.
• (software compilation) Clipping of naming collision. [(software compilation) An error caused by two source code elements (such as variables or functions) having the same name as each other.]
• (computing, chiefly video games) Clipping of collision detection; tangibility. [(computing, chiefly video games) The process or mechanism of determining whether two shapes are partially occupying the same space.]