I have thought of a 6 letter word:
_ _ _ _ _ _
but I'm not going to tell you what it is. Instead you give me 6 letter words, and I mark them according to the normal rules of Mastermind.
A 'word' can be garbage if you want, e.g. PZQABC, or a normal word like BUTTER. These get marked as 0r1w and 0r2w respectively. The answer word is a real word in this case.
I don't know how hard this is, so here's a few more. If no-one can get it, I'll add more until someone does.
- PESTLE 2r0w
- VIOLIN 0r0w
- PUZZLE 1r1w
- CAMERA 0r2w
- HELIUM 1r1w
- OXYGEN 0r1w
- BANANA 0r0w