Source : Webster's Revised Unabridged Dictionary (1913)

Myriagram \Myr"i*a*gram\, Myriagramme \Myr"i*a*gramme\, n. [F.
   myriagramme. See {Myria-}, and 3d {Gram}.]
   A metric weight, consisting of ten thousand grams or ten
   kilograms. It is equal to 22.046 lbs. avoirdupois.

Source : WordNet®

myriagram
     n : one ten thousandth of a centner [syn: {myg}]