Source : Webster's Revised Unabridged Dictionary (1913)

Milreis \Mil"reis`\, n. [Pg. mil reis, i. e., one thousand reis;
   mil a thousand + reis, pl. of real a rei.]
   A Portuguese money of account rated in the treasury
   department of the United States at one dollar and eight
   cents; also, a Brazilian money of account rated at fifty-four
   cents and six mills.