Definition of affordances:
(n) :
(human-machine interaction) A potential transaction or operation that is made possible by a given object or environment; especially, one that is made easily discoverable.
(n) :
(graphical user interface) Any interactive control or component serving as a cue to the user to take some action.
(n) :
(psychology, philosophy, robotics) Anything that is provided or furnished by an environment to an organism dwelling within it.