Conundrum: a difficult puzzle or problem. A seemingly unsolvable problem.
A conundrum is also a riddle with an answer containing a pun. In my research, I kept running across this example: What’s the difference between a jeweler and a jailer? One sells watches and the other watches cells.
No one knows for sure where the word conundrum comes from. It’s a conundrum, ironically.
Some say students at Oxford University may have simply coined a Latin sounding word. In other words, conundrum is a made up, Latin sounding word. Like hocus-pocus, which is also a made up Latin word. These words are known as pseudo-Latin.
Synonyms help. A conundrum is an enigma, a riddle, a mystery, a puzzle, a problem.