If two or more moving people or objects collide, they crash into one another. If a moving person or object collides with a person or object that is not moving, they crash into them. Two trains collided head-on in north-eastern Germany early this morning Racing up the stairs, he almost collided with Daisy He collided with a pine tree near the North Gate
If the aims, opinions, or interests of one person or group collide with those of another person or group, they are very different from each other and are therefore opposed. The aims of the negotiators in New York again seem likely to collide with the aims of the warriors in the field What happens when the two interests collide will make a fascinating spectacle. = clash