IPA: //prɪˈpɛrətər//
KK: /prɪˈpɛrətər/
A person who gets things ready, especially for scientific study or display, like in a museum.
The preparator carefully arranged the fossils for the exhibition.
Preparator is formed from "pre-" (meaning before) and "parare" (meaning to prepare). The word refers to someone who prepares something in advance.
Think of someone who is getting things ready 'before' ('pre-') an event — that's what a preparator does.