Originally published 10/15/2012

Okay, y’all, I originally posted this seven and a half years ago, and my call for actual evidence to support the claim below netted me nothing but others who were curious, LOL. So I’m trying again–because this claim has since even appeared on Big Bang Theory, touted by Sheldon. So, seriously, people. Someone defend the claim, or I shall be forced to call Sheldon a liar. ๐Ÿ˜‚
So here’s the deal. I’ve heard from quite a few sources that we moderns are misusing the word nauseous. That it ought not to mean “to feel sick or queasy” but that it rather means “to cause a feeling of nausea.”
Now, I’ve heard this from sources I trust, but they never quote their sources, and I’m now on a quest to figure out why in the world this is touted as grammatical fact and, more, as a “modern mistake” when every dictionary I look it up in says that nauseous has carried both meanings (“to feel sick” and “to make sick”) since 1600-1610.
One dictionary I found says “careful writers will use nauseated for the feeling of queasiness and reserve nauseous for ‘sickening to contemplate.'” I’m okay with being careful, really I am, but I’m still unsure why grammarians are saying that using its original meaning is “a mistake of the moderns.” It is, in fact, the first definition of the word in the OED.
So. Calling all grammarians! ๐Ÿ˜‰ If you learned it this way and could point me to a source (not just an expert like the wonderful Grammar Girl, mind you) that states this as fact, I would be very grateful. I don’t mind changing my ways to be a “careful” writer–but I’m a Johnnie. I don’t ever accept an expert’s opinion without checking out their sources. ๐Ÿ˜‰