Learn about the definition, types, and analysis of mechanisms in engineering. A mechanism is a device that transforms input forces and movement into a desired set of output forces and movement, using links and kinematic pairs. The mechanism of enzyme action is related with the enzyme ’s specificity and the transition state of the reactants or substrates. Use the word mechanism to describe a process that has been set up to accomplish a particular goal. If you’ve set up a method for dealing with your sister when she annoys you, then you have a mechanism in place for establishing peace with your sister. The meaning of MECHANISM is a piece of machinery. How to use mechanism in a sentence.