impact
n. C / Un. a strong effect or influence that something has on a situation or person. It can also mean the physical force of one object hitting another.
n. a marked effect or influence upon a situation, person, or system. It also describes the physical force or action of one object coming into forcible contact with another.
The new policy has a huge impact on local businesses.
The environmental impact of the oil spill was devastating, leaving thousands of marine animals struggling to survive along the coast.
While the immediate physical impact of the crash was minor, the psychological trauma left a lasting impression on the driver, fundamentally altering her approach to road safety.
Often followed by the preposition 'on' or 'upon' when describing an effect.