Originally Posted by unterhausen

There seems to be an international split in the vibration engineering community over "damping" vs. "dampening." In the U.S., vibration engineers generally assert that "dampening" is the process of getting something wet. But outside the U.S., "dampening" is often used to mean something that removes energy from a vibrating system. Both words have the same root, so it's difficult to make an argument either way based on linguistics.