Most of us will recognize the name acetaminophen, commonly seen on the labels of generic brand alternatives to Tylenol. But I only recently learned of the two words’ common origin. It turns out that both names, Tylenol and acetaminophen, come from different parts of the drug’s less used chemical name, para-acetylaminophenol:


I think it’s amusing that the parts used by each name are nearly inverse components of the original word. I don’t know when each word came into use, but it makes me wonder whether one was deliberately chosen to be as different as possible from the other.