Threshold concepts are transformative, irreversible, integrative, bounded, and potentially troublesome “conceptual gateways” or “‘portals’ that lead to a transformed view of something” (Meyer & Land, 2006, p. 19).
Transformative: Once understood, a threshold concept changes the way in which the student views the discipline.
Irreversible: Given their transformative potential, a threshold concept is also likely to be difficult to unlearn.
Integrative: In understanding the concept, the learner will be exposed to the previously hidden interrelatedness of different aspects of the discipline.
Bounded: The threshold concept helps to define the boundaries of a subject area.
Troublesome: Each concept may be counterintuitive so, in grasping a threshold concept the learner may move to an understanding that goes against and beyond previous or common-sense knowledge.