collidephoneticPhoneticPhoneticPhoneticPhoneticPhoneticPhoneticPhoneticphonetic verb [I]
(esp. of moving objects) to hit (something) violently
The two vans collided (with each other) at the crossroads.
It was predicted that a comet would collide with one of the planets.
The bike collided into a tree.

collisionphoneticPhoneticPhoneticPhoneticPhoneticPhoneticPhoneticPhoneticPhoneticPhoneticphonetic noun [C]
There has been a collision involving a number of cars on the main road into town. [C]
Two drivers were killed in a head-on (=direct) collision between a car and a taxi last night. [C]

If two or more people or organizations are on a collision course there will probably soon
be a fierce disagreement.
The director and his staff are on a collision course.

This page is cited from Cambridge Dictionaries Online. For the original, please visit

http://dictionary.cambridge.org/define.asp?key=collide*1+0