Hat-maker was my first guess, too, but that's milliNer. I think some of freerice's definitions are a little iffy, I wouldn't use it as great vocabulary building tool. One other example is organum which it defines as Gregorian chant. OK, some organum is based on Gregorian chant, but organum is polyphonic and chant is monophonic. Organum is a step beyond Gregorian chant.

Oh, and FWIW, millier