The Collaborative International Dictionary of English v.0.48:

Cowan \Cow"an\ (kou"an), n. [Cf. OF. couillon a coward, a
   cullion.]
   One who works as a mason without having served a regular
   apprenticeship. [Scot.]

   Note: Among Freemasons, it is a cant term for pretender,
         interloper.
         [1913 Webster]

U.S. Gazetteer Places (2000):

Cowan, TN -- U.S. city in Tennessee
   Population (2000):    1770
   Housing Units (2000): 803
   Land area (2000):     1.976428 sq. miles (5.118926 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    1.976428 sq. miles (5.118926 sq. km)
   FIPS code:            17700
   Located within:       Tennessee (TN), FIPS 47
   Location:             35.166668 N, 86.011839 W
   ZIP Codes (1990):     37318
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Cowan, TN
    Cowan