The Collaborative International Dictionary of English v.0.48:

Popper \Pop"per\, n.
   A utensil for popping corn, usually a wire basket with a long
   handle.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Popper \Pop"per\, n.
   A dagger. [Obs.] --Chaucer.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Popper
    n 1: British philosopher (born in Austria) who argued that
         scientific theories can never be proved to be true, but are
         tested by attempts to falsify them (1902-1994) [syn:
         Popper, Karl Popper, Sir Karl Raimund Popper]
    2: a container of stimulant drug (amyl nitrate or butyl nitrite)
    3: a container for cooking popcorn