The Collaborative International Dictionary of English v.0.48:

Calvin \Cal"vin\ n.
   1. John Calvin, a French theologian and reformer; born 1509,
      died 1564.
      [WordNet 1.5]

WordNet (r) 3.0 (2006):

Calvin
    n 1: United States chemist noted for discovering the series of
         chemical reactions in photosynthesis (1911-) [syn:
         Calvin, Melvin Calvin]
    2: Swiss theologian (born in France) whose tenets
       (predestination and the irresistibility of grace and
       justification by faith) defined Presbyterianism (1509-1564)
       [syn: Calvin, John Calvin, Jean Cauvin, Jean Caulvin,
       Jean Chauvin]

U.S. Gazetteer Places (2000):

Calvin, ND -- U.S. city in North Dakota
   Population (2000):    26
   Housing Units (2000): 19
   Land area (2000):     0.217911 sq. miles (0.564388 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.217911 sq. miles (0.564388 sq. km)
   FIPS code:            11700
   Located within:       North Dakota (ND), FIPS 38
   Location:             48.851162 N, 98.937397 W
   ZIP Codes (1990):     58323
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Calvin, ND
    Calvin


U.S. Gazetteer Places (2000):

Calvin, OK -- U.S. town in Oklahoma
   Population (2000):    279
   Housing Units (2000): 144
   Land area (2000):     0.482229 sq. miles (1.248967 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.482229 sq. miles (1.248967 sq. km)
   FIPS code:            11100
   Located within:       Oklahoma (OK), FIPS 40
   Location:             34.967315 N, 96.249811 W
   ZIP Codes (1990):     74531
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Calvin, OK
    Calvin


U.S. Gazetteer Places (2000):

Calvin, LA -- U.S. village in Louisiana
   Population (2000):    236
   Housing Units (2000): 111
   Land area (2000):     2.287907 sq. miles (5.925652 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    2.287907 sq. miles (5.925652 sq. km)
   FIPS code:            11930
   Located within:       Louisiana (LA), FIPS 22
   Location:             31.963299 N, 92.779853 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Calvin, LA
    Calvin