v. describing the behavior, generally displayed by those with various developmental disabilities, of extraordinary, exclusive and lasting obsession to a detail or occurrence others consider minor.
v. to repeat or continue a pattern.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
v. psychology: repeat a response after the cessation of the original stimulus
Word Usage
"This propensity to perseverate is sometimes self-destructive, as when I am unable to stop practicing a single piece on the piano or to quit solitaire, but"