Good grief. Crash landing. Cheerful pessimist.
These words are examples of oxymorons. An oxymoron is a figure of speech in which two words with contradictory meanings are placed side-by-side. Take "good grief." Grief isn't traditionally thought of as good, so the words are a paradox.
Some oxymorons are so common that you might not even realize they're inherently contradictory. For instance, if you've ever replied to a party invitation with, "I'm a definite maybe," then you're using an oxymoron.
Writers have been using oxymorons for hundreds of years to express humor or irony. Shakespeare's famous line, "Parting is such sweet sorrow," is a great example. "Sorrow" typically isn't thought of as "sweet." Paul Simon's famous song, "The Sound of Silence," is another example of an oxymoron: how can silence have a sound?
Oxymorons have been around forever. Here's a list of 25 of our favorites.
What do you think? Did that list surprise you? I, for one, totally forgot that "plastic silverware" is an oxymoron. Let us know if we captured your favorite oxymorons in the comments.