This prompt takes me back to my high school days when we were taught literature, the figures of speech. I really loved it back then, and the figurative expressions were cool.
One of such is oxymoron, bringing two words with opposite meaning together. The words now become one, so it doesn't have a meaning at the point but it can be used in a context. So many like that, bittersweet, hotcold, and the likes. It just help us express how we feel.
The participation link:
@mariannewest/day-1829-5-minute-freewrite-tuesday-prompt-bittersweet