Definitions
There are 2 meanings of the phrase
Collision Course.
Collision Course - as a noun
A course of a moving object that will lead to a collision if it continues unchanged
A course of action (following a given idea) that will lead to conflict if it continues unabated
Example Sentences
"The two cars were on a collision course and crashed into each other."
"The diver and the swimmer were on a collision course and collided in the pool."
"The airplane and the bird were on a collision course but narrowly avoided a crash."
"The cyclist and the pedestrian were on a collision course, but the cyclist swerved at the last moment."
"The ship and the iceberg were on a collision course, leading to a disaster."