What is the synonym of etymology?

There isn't one perfect synonym for "etymology," as it has a very specific meaning. However, depending on the context, you could use:

* Word origin: This is a more general term that encompasses the study of the history and development of words.

* Word history: Similar to "word origin," but with a slightly broader focus.

* Linguistic history: This term emphasizes the study of language development and evolution.

* Derivation: This focuses specifically on the process of how a word is formed from other words.

Ultimately, the best synonym will depend on the specific situation and the intended meaning.