This is one of my favourite words in the English language because it’s simple, sophisticated, precise, and a bit mysterious, all at the same time.
Far from just being a character name in Batman, this is a great way to politely describe someone or something that confuses you. Instead of complaining that you simply don’t get so-and-so’s actions, say that you find their behaviour enigmatic. Instant grown-up! And you won’t sound petty.