The Collaborative International Dictionary of English v.0.48:

Rupee \Ru*pee"\ (r[.u]*p[=e]"), n. [Hind. r[=u]piyah, fr. Skr.
   r[=u]pya silver, coined silver or gold, handsome.]
   A silver coin, and money of account, in the East Indies.
   [1913 Webster]

   Note: The valuation of the rupee of sixteen annas, the
         standard coin of India, by the United States Treasury
         department, varies from time to time with the price of
         silver. In 1889 it was rated at about thirty-two cents.
         [1913 Webster]

WordNet (r) 3.0 (2006):

rupee
    n 1: the basic unit of money in Sri Lanka; equal to 100 cents
         [syn: Sri Lanka rupee, rupee]
    2: the basic unit of money in Seychelles; equal to 100 cents
       [syn: Seychelles rupee, rupee]
    3: the basic unit of money in Nepal; equal to 100 paisa [syn:
       Nepalese rupee, rupee]
    4: the basic unit of money in Mauritius; equal to 100 cents
       [syn: Mauritian rupee, rupee]
    5: the basic unit of money in Pakistan; equal to 100 paisa [syn:
       Pakistani rupee, rupee]
    6: the basic unit of money in India; equal to 100 paise [syn:
       Indian rupee, rupee]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

RUPEE, comm. law. A denomination of money in Bengal. In the computation of
ad valorem duties, it is valued at fifty-five and one half cents. Act of
March 2, 1799, s. 61; 1 Story's L. U. S. 627. Vide Foreign coins.
     2. The rupee of British India as money of account at the custom-house,
shall be deemed and taken to be of the value of forty-four and one half
cents. Act of March 3, 1848.