Even those who pride themselves on their English skills and believe that they know the meaning of just about all the words in the English language can struggle with knowing true definitions. Some words are so complicated that you just have no idea what they could possibly mean. Others sound too similar to a word that you do know, and you get confused between their meanings. Then there are those false friends, who sound like they pertain to one thing but they actually have nothing to do with it and mean something totally different. Basically, even English professors have trouble with certain words! The only problem is that some of these words are extremely common, and not knowing what they mean when they come up in conversation is, well, embarrassing. So how many of these notoriously tricky words do you know? Do you know what it means when someone goes on a tirade? How about what it means to vilify someone? Do you know when to really describe something as being quaint, or when a person is really being negligent and when they're not? Do you know what sobriety means, or what a maxim actually is? How about what exactly constitutes a litigant, and when you can be classified as really foiling someone's plans? Take this quiz to find out if you really know the difference between debacle and rife, and what it means to instigate something. Find out how much you really know about some of the hardest words in the English language now!