Thanks--atheists and theists often commit this fallacy labeling the terms: Atheist, theist, and agnostic--https://www.thoughtco.com/etymological-fallacy-words-1690613
My favorite parts from your source regarding the 'etymological fallacy':
"One thing to remember when you read or hear someone insisting that an English word must have a certain meaning because of its Latin or Greek roots is that these insisters apply their etymologies very selectively. You will find few of them who object to December being used for the twelfth month, when its Latin root means 'ten,' or to manure being used as a noun meaning 'to work (land) by hand.' So when you read, for example, that caption must refer to matter above a picture because it comes from Latin caput 'head,' keep manure in mind."