1) An event produced by some other event, especially, in operant contexts, an event produced by a response. It might include stimulus presentation or removal, a change in contingencies, or any other alteration of the environment. The term is particularly useful for referring to stimuli with an unknown status as reinforcers or punishers (presenting such events contingent upon responding has sometimes been called consequation).

2) An environmental event or stimuli that occurs immediately after a response.

3) AN environmental events that occurs after a behavior. (Consequence that is not produced by the behaviour are called adventitious.)