Source : Webster's Revised Unabridged Dictionary (1913)

Mon \Mon\, n. [Jap.] (Japan)
   The badge of a family, esp. of a family of the ancient feudal
   nobility. The most frequent form of the mon is circular, and
   it commonly consists of conventionalized forms from nature,
   flowers, birds, insects, the lightnings, the waves of the
   sea, or of geometrical symbolic figures; color is only a
   secondary character. It appears on lacquer and pottery, and
   embroidered on, or woven in, fabrics. The imperial
   chrysanthemum, the mon of the reigning family, is used as a
   national emblem. Formerly the mon of the shoguns of the
   Tokugawa family was so used.

Source : WordNet®

Mon
     n 1: the second day of the week; the first working day [syn: {Monday}]
     2: a member of a Buddhist people living in Myanmar and adjacent
        parts of Thailand
     3: the Mon-Khmer language spoken by the Mon people