Allow us to start with some simple definitions: this article concerns prefixing a single letter to a root word (root for short) to make another word, e.g., M prefixes the root AN to make MAN. In the January 1997 Wordsworth, Ted Clarke asked whether there was a longer set of four-letter words than a list of 16 based on IND as the last three letters.
Gooch, Rex and Thorpe, Susan
"Single Letter Prefixing,"
Word Ways: Vol. 31
, Article 13.
Available at: https://digitalcommons.butler.edu/wordways/vol31/iss4/13