degeneracy
limiting case in which an element of a class of objects is qualitatively different from the rest of the class
en-GB/dɪˈd͡ʒɛnəɹəsɪ/
en-US/dɪˈd͡ʒɛnɚəsi/
limiting case in which an element of a class of objects is qualitatively different from the rest of the class