: the quality or property of an object that defines its possible uses or makes clear how it can or should be used
We sit or stand on a chair because those affordances are fairly obvious. Scott Lafee
An affordance is a resource or support that the environment offers an animal; the animal in turn must possess the capabilities to perceive it and to use it. Eleanor J. Gibson et al.
Note: As a term in the study of cognition introduced by the American psychologist James J. Gibson (1904-79) in The Senses Considered as Perceptual Systems (Boston, 1966) and later essays.