All permutations of a string for the teacher's sake

Today my kid brought back from school an assignment to guess words from a bag of letters... it took a mum and a programmer to solve all six. I left one for you, though. Guess what C D E E I M R R stands for.

P.S. it's a classical programming interview question about all permutations of a string. Generate all permutations, grep -f them against /usr/share/dict/french and you'll get the answer.