collision

American  

[kuh-lizh-uhn] / kəˈlɪʒ ən /

noun

1. the act of colliding; a coming violently into contact; crash.

   the collision of two airplanes.

2. a clash; conflict.

   a collision of purposes.

3. Physics. the meeting of particles or of bodies in which each exerts a force upon the other, causing the exchange of energy or momentum.

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collision British  

/ kəˈlɪʒən /

noun

1. a violent impact of moving objects; crash

2. the conflict of opposed ideas, wishes, attitudes, etc

   a collision of interests

3. physics an event in which two or more bodies or particles come together with a resulting change of direction and, normally, energy

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Other Word Forms

• anticollision
  adjective
• collisional
  adjective

Etymology

Origin of collision

1400–50; late Middle English < Late Latin collīsiōn- (stem of collīsiō ), equivalent to collīs ( us ) (past participle of collīdere to collide ) + -iōn- -ion

Explanation

A collision is when two or more things smash together. You shouldn't give yourself a pedicure while driving because it might result in a collision, wrecking your car and spoiling your toenail polish to boot. Collision comes from the Latin col-, "together," and lædĕre, "to hurt by striking." When a train hits a car, that's a collision. An asteroid hurtling toward earth is on a "collision course" with our planet. Collision also works for abstract conflicts that get violent or hurt your brain somehow, like the collision between two politicians during a debate, or the collision of colors in your outfit.

Example Sentences

Migrating gray whales and ships are on a collision course in the San Francisco Bay, with at least seven whales dead so far this year—many from vessels—after 21 fatalities in 2025.

From The Wall Street Journal • May 19, 2026

According to new research, the famous work could also represent an early thought experiment in impact physics, describing a catastrophic planetary collision centuries before modern meteor science existed.

From Science Daily • May 11, 2026

Conflicts in the Middle East are increasing dangers for whales off South Africa by shifting sea traffic into their habitats and heightening the risks of collision, researchers told AFP.

From Barron's • May 11, 2026

"To avoid this collision course the government needs to step up and deliver the properly funded education system our children and young people deserve."

From BBC • May 9, 2026

Beside it was the splintered body of a tree, still rolling to a stop after the collision.

From "The Darkest Minds" by Alexandra Bracken