momon m (plural momons)
A term of very complicated etymology.
Almost certainly cognate with German Mumme (“mask”), Dutch mom (“mask”), Spanish momo (“grimace”).
Perhaps ultimately of the same origin as mum, with which momon's derived forms mommer (“to wear a mask”) and momeor were often conflated when Germanic languages attempted to borrow them (compare and see "mummer"). If they are ultimately of the same origin, then it would likely be because the muffled sound that one would make while wearing a mask would be nearly identical to the "mmm" sound a mime might make while trying to remain silent. If that is the case, then the term is ultimately of onomatopoeiac origin.
Indeed, note Middle Low German mummen (“to speak indistinctly, to disguise oneself”), Dutch mommen (“to speak indistinctly”), German mummen (“to speak indistinctly”), English mump (“to grimace, mumble”).
momon oblique singular, m (oblique plural momons, nominative singular momons, nominative plural momon)