The Collaborative International Dictionary of English v.0.48:

Lama \La"ma\, n. [Tibet. blama (pronounced l[aum]"ma) a chief, a
   high priest.]
   In Tibet, Mongolia, etc., a priest or monk of the belief
   called Lamaism.
   [1913 Webster]

   The Grand Lama, or Dalai Lama [lit., Ocean Lama], the
      supreme pontiff in the lamaistic hierarchy. Until the
      Chinese occupied Tibet he resided in Lhasa, but now (1998)
      is in exile. See Lamaism.
      [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

Dalai Lama
    n 1: chief lama and once ruler of Tibet [syn: Dalai Lama,
         Grand Lama]