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 (19 January 2023):

Klamath

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

   (1998-09-07)