Formal/Academic:
* Neologist: This is the most common and precise term, directly derived from "neology" which means "the creation of new words."
* Lexicographer: This term is generally used for someone who compiles dictionaries, but it can also encompass those who create new words, especially if they contribute to lexicography.
* Etymologist: This term is for someone who studies the origins and historical development of words. They may sometimes create new words to fill gaps in language or represent new concepts.
Informal/Creative:
* Wordsmith: This term is more general and can refer to anyone who is skilled with language, including those who create new words.
* Inventor (of words): This is a simple and direct term that can be used in casual contexts.
* Language innovator: This term emphasizes the innovative aspect of creating new words and its impact on language.
The best term to use will depend on the specific situation and the desired level of formality.