The Collaborative International Dictionary of English v.0.48:

Muller \Mull"er\, n.
   1. One who, or that which, mulls.
      [1913 Webster]

   2. A vessel in which wine, etc., is mulled over a fire.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Muller \Mull"er\, n. [OE. mullen to pulverize, bruise; cf. Icel.
   mylja; prob. akin to E. mold soil. See Mold soil, and cf.
   Mull dirt.]
   A stone or thick lump of glass, or kind of pestle, flat at
   the bottom, used for grinding pigments or drugs, etc., upon a
   slab of similar material.
   [1913 Webster] Mullerian

WordNet (r) 3.0 (2006):

Muller
    n 1: Swiss chemist who synthesized DDT and discovered its use as
         an insecticide (1899-1965) [syn: Muller, Paul Hermann
         Muller]
    2: Swiss physicist who studied superconductivity (born in 1927)
       [syn: Muller, Karl Alex Muller]
    3: German physiologist and anatomist (1801-1858) [syn: Muller,
       Johannes Peter Muller]
    4: German mathematician and astronomer (1436-1476) [syn:
       Muller, Johann Muller, Regiomontanus]
    5: British philologist (born in Germany) who specialized in
       Sanskrit (1823-1900) [syn: Muller, Max Muller, Friedrich
       Max Muller]
    6: United States geneticist who studied the effects of X-rays on
       genes (1890-1967) [syn: Muller, Hermann Joseph Muller]
    7: a reflective thinker characterized by quiet contemplation
       [syn: muser, muller, ponderer, ruminator]
    8: a heavy tool of stone or iron (usually with a flat base and a
       handle) that is used to grind and mix material (as grain or
       drugs or pigments) against a slab of stone [syn: pestle,
       muller, pounder]
    9: a vessel in which wine is mulled