Definition from Wiktionary, the free dictionary
completist (plural completists)
- A collector who strives to obtain a complete collection of some type of thing.
- A person who champions any philosophy which somehow includes the completeness of something; as, a completist philosopher who holds that a definite complete body of knowledge exists to be discovered
completist (not comparable)
- Which attempts to collect something completely; as, a completist dictionary, a completist collector