I chose "puzzle" as a medium-difficulty word for Hangman. At 6 letters, it meets the length requirement. It contains an uncommon letter (z) that appears twice, making it challenging but not impossible. It's a common enough word that most people would know, but the repeated 'z' and the combination of letters make it tricky enough to be interesting. The word follows all the rules: it's a real English word, uses only letters a-z, has no spaces or special characters, and isn't a proper noun or acronym.