"EDNOTE. Nabokov's Latin was mostly based in Linnean taxonymy terms.
Although W.T. Stern's standard BOTANICAL LATIN does not specifically give the term patifolia, PAT- often has the meaning 'broad'. Hence "patifolia" would mean something like "broad leaf"--a suitable descriptive term for Kinbote's play pillow.
For other needs than sleep Charles Xavier had installed in the middle of
> the Persian rug-covered floor a so-called patifolia, that is, a huge, oval,
> luxuriously flounced, swansdown pillow the size of a triple bed"--