The Collaborative International Dictionary of English v.0.48:

Maumnnerchor \M[aum]n"ner*chor`\, n.; G. pl.
   M[aum]nnerch["o]re. [G.; m[aum]nner, pl. of mann man + chor
   chorus.]
   A German men's chorus or singing club.
   [Webster 1913 Suppl.]