The August 1979 Word Ways article "Word Roots and Branches" showed how the 17-letter Websterian word ANTICEREMONIALIST could be successively transdeleted down to a single letter: remove E and rearrange the remaining 16 letters to obtain NONMATERIALISTIC, remove N and rearrange the remaining 15 letters to obtain RECITALIONALISM, and so on. Unfortunately, it was necessary to include one non-Websterian word, RECLAMATIONIST (used in 1946 Saturday Evening Post article), in the sequence.
Eckler, A. Ross
"Two New Transdeletion Pyramids,"
Word Ways: Vol. 21
, Article 4.
Available at: https://digitalcommons.butler.edu/wordways/vol21/iss2/4