Recently, English Professor Anne Curzan was giving a talk in Washington about reduplication. In reduplication, a form is repeated in a straightforward way, like "no-no" or "boo-boo," or with a vowel change like "flip-flop" or "mish-mash." During Curzan's talk, someone in the audience raised their hand and said, "You keep using the word 'reduplication.' Isn't that redundant? Why don't you just say 'duplication'?" Fair question.