The Collaborative International Dictionary of English v.0.48:

Klamaths \Kla"maths\, prop. n. pl.; sing. Klamath (Ethnol.)
   A collective name for the Indians of several tribes formerly
   living along the Klamath river, in California and Oregon, but
   now restricted to a reservation at Klamath Lake; -- called
   also Clamets and Hamati.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Klamath
    n 1: a river flowing southwest from Oregon through northern
         California to the Pacific Ocean [syn: Klamath, Klamath
         River]

The Free On-line Dictionary of Computing (30 December 2018):

Klamath

    The pre-release "code name" for Intel's Pentium
   II microprocessor.

   (1998-09-07)


U.S. Gazetteer Counties (2000):

Klamath -- U.S. County in Oregon
   Population (2000):    63775
   Housing Units (2000): 28883
   Land area (2000):     5944.186082 sq. miles (15395.370621 sq. km)
   Water area (2000):    191.560791 sq. miles (496.140150 sq. km)
   Total area (2000):    6135.746873 sq. miles (15891.510771 sq. km)
   Located within:       Oregon (OR), FIPS 41
   Location:             42.662031 N, 121.651634 W
   Headwords:
    Klamath
    Klamath, OR
    Klamath County
    Klamath County, OR


U.S. Gazetteer Places (2000):

Klamath, CA -- U.S. Census Designated Place in California
   Population (2000):    651
   Housing Units (2000): 365
   Land area (2000):     12.535989 sq. miles (32.468061 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    12.535989 sq. miles (32.468061 sq. km)
   FIPS code:            38702
   Located within:       California (CA), FIPS 06
   Location:             41.533075 N, 124.014866 W
   ZIP Codes (1990):     95548
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Klamath, CA
    Klamath