from Fancyclopedia 1 ca. 1944
The word comes from Dali-istic painting, where it designates drawings in which seemingly symbolic things are scattered about without there actually being any meaning intended in the pictures. If it can be used of literature, it applies to alien-sounding double-talk like this: Gram spramphis tham stampistan gram hendis stan tha gramdorcax importistan (Kornbluth), and poetry like this:

Bayar, the iddy lamp comes plug-plug
See the wrong side upway man avar
So mags the dulcet simper of a rimy rug
And dents the skin smooth softness of the jar.
(RoyS & JohnLeC)

The resemblance to metaphysical poetry is apparent.