perdurantist \per*dur"ant*ist\ (p[~e]r*d[=u]r"ant*[i^]st), n.
(Philosophy)
A philosopher who considers the fundamental objects of the
real world as extended in the direction of time, so that the
objects themselves do not change, though temporal parts may
have different properties. Contrasted to {endurantist}, one
who considers objects to be wholly present at each instant.
[PJC]