transdifferentiation Syllabification: (trans·dif·fer·en·ti·a·tion)Pronunciation: /tranzˌdifəˌrenSHēˈāSHən, trans-/Definition of transdifferentiation noun Biology the rare natural transformation of cells other than stem cells into a different cell type. Derivatives transdifferentiatePronunciation: /-SHēˌāt/ verb [no object]