Wiktionary
involutional
a. 1 of or pertaining to involution 2 characterized by involution
WordNet
Wikipedia
Usage examples of "involutional".
At the time of our own Civil War the chief carrier was that sufferer from involutional melancholia, that tormented man from whom knives once had to be hidden, Abraham Lincoln.
It stood as a grudging tribute to the months he had held out against involutional melancholia in the yute Blank Tanks.