"Jenner wondered if the pus from the milkmaid's cowpox blisters was somehow preventing them from contracting smallpox," McFedries said.
To test this hypothesis, Jenner extracted some cowpox pus and inoculated an 8-year-old girl with it (a practice that would now be deemed unethical in the practice of medical studies).
Jenner found that the cowpox virus did make the little girl immune to smallpox. In naming this new medical advancement, Jenner turned to classical Latin.
He called his injection the "vaccine virus". The word vaccine is derived from the Latin word "vacca" meaning cow.
"By 1846, the word vaccine was in general use as any substance that inoculates against a disease," McFedries said.
We are all familiar with the nasty signs of nausea, feeling queasy and having the unwanted urge to bury your head in a toilet to vomit.
We know it to mean "you're not feeling exactly ship-shape," McFedries said.
"That's true physically, but it's also true etymologically," McFedries added.
The word "nausea" has Greek origins, where their term for seasickness was nausia. This term is actually a combination of two words in the Greek language -- naus meaning ship and the suffix -ia meaning sickness.
When put together, the word nausia literally means ship sickness, referring to that uneasy feeling that some may get after staying too long on a rocking boat.
We now use it as a word to signify the symptom of wanting to throw up, whether you're on a ship or not.
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