Compulsive repetition of an act until perfect.

The word itself is a neologism, as it doesn't appear in the OED. It is modeled after paranoia, using Greek roots: palin, again + nous, noos, mind. Mainly used by fans of obscure words, including the writers of Pinky and the Brain.

An honest flow from our heart in spirit and truth is pleasing to our LORD, but I doubt that He is pleased with a "pouring out" of fancy phrases, platitudes, or vain liturgical palinoia.
Bill Vaught, "Offering." October 1993. Keystone Christian TALK. <http://keystone-christian.com/talk/archives/363> (September 13, 2012)

One of the classic forms of the condition is of course the dogged piano practice of the freckled ten-year-old next door.... The technical term for this is pianola palinoia, and the condition brought on in the listener is known as pianola palinoia paranoia.
Peter Bowler, The Superior Person's Book of Words. Boston: David R. Godine, 1979.