In English words, cum has produced the prefixes com-, con-, and col-. These prefixes convey the idea of “together, together with, in combination or union.” For example, the noun companion combines com- with panis (bread). A companion is “a person to eat bread with.” Sharing a meal with someone is often a sign of intimacy.
Collision comes from the verb collide (col + laedere). The Latin verb laedere means “to injure” or “to damage.” When things collide, they strike or clash together.
Collusion comes from the verb collude (col + ludere), The Latin verb ludere means, “to play.” When people collude, they “play” together. The kind of play meant here is not the friendly kind. It’s the deceptive activity implied in the expressions “to play at,” “to play one false,” and “to play into someone’s hands.”
Collision is “the violent encounter of a moving body with another.” On the street, a collision usually involves vehicles. In physics, particles collide. Both collision and collide are used figuratively to indicate a clash of wills. The noun collision may also be used attributively (i.e., to modify another noun). Here are examples of usage:
Both of the Washington State Patrol troopers injured in collisions Sunday night near Northgate have been released from the hospital.
Two Metro-North Railroad trains collided after a derailment near Fairfield, Conn., at the height of the evening rush on Friday.
Somalia: What happens when political and humanitarian goals collide?
Global Markets and National Politics: Collision Course or Virtuous Circle?
Collusion is a secret agreement for purposes of trickery or fraud. In law, collusion is an agreement between two or more parties for the purpose of defrauding others or to gain an unfair market advantage, for example, price-fixing and inside trading. Here are some recent headlines:
Big Tech Companies Agree To Pay Up Over Hiring Collusion
Shell and BP accused of collusion in South Africa
How Hospitals and Health Insurers Collude at Your Expense
Business and Government Collude over Education Policy and Funding
Courtesy: Daily Writing Tips