I heard it again today: someone complaining that they were nauseous. I had to giggle. You see, I used to use nauseous in this fashion too, until I discovered what it actually means:
Nauseous: Causing nausea; sickening (per dictionary.com)
So, when you complain of being nauseous, you are admitting that you are so repulsive that you sicken those around you - probably not what you meant.
If you’re feeling queasy, the correct term is nauseated. (Nauseated, interestingly, means both to feel and to cause nausea!)
I don’t mean to sound supercilious. I just want to educate the nauseous people of the world. Blech!