There are many terms that are used to describe situations in which multiple disciplines work together. These include Cross-Disciplinary, Inter-Disciplinary, Multi-Disciplinary, and Trans-Disciplinary. These terms are related, but they aren't the same.
When one scientist working in one discipline (Biology, for example) solves a problem, the work is Discipilinary - just one discipline was involved.
When two or more scientists from different disciplines (Biology, Engineering, and Design, perhaps) work independently on different aspects of the same problem, the work is Multi-Disciplinary. The team worked together and perhaps learned from each other, but everyone viewed the problem from their own disciplinary perpective.
If, however, the team works together on the same aspects of the same problem, sharing ideas and techniques from their own fields, and in doing so, learn to view the problem from each other's perspectives, it's Inter-Disciplinary.
If this same team goes one step further and begins to think outside their disciplines and focus instead on discovering what information is needed to solve the problem, then they will begin to see new ideas, new techniques, and new ways of solving the problem. When this occurs, their work becomes Trans-Disciplinary. The work the team does now transcends any one of the disciplines.
If Inter-Disciplinary work is a mixing of disciplines, then Trans-Disciplinary work is a fusion of disciplines.
At the University level, professors who see the benefit of working in Trans-Disciplinary groups usually work both inside and outside Academia - they often partner with external stakeholders like community and industry leaders who have really wicked problems that need solutions - solutions that cannot be found within a single discipline.
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"Transdisciplinarity may be understood, metaphorically, as a process of composting that leads to the creation of fertile soil in which new knowledge and applications may be cultivated."
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