The Collaborative International Dictionary of English v.0.48:

Philopena \Phil`o*pe"na\, n. [Probably a corruption fr. G.
   vielliebchen, LG. vielliebken, or D. veelliebken, a
   philopena, literally, much loved; but influenced by Gr.
   fi`los a friend, and L. poena penalty, from an idea that the
   gift was a penalty of friendship or love.]
   A present or gift which is made as a forfeit in a social game
   that is played in various ways; also, the game itself.
   [Written also fillipeen and phillippine.]
   [1913 Webster]

   Note: One of the ways may be stated as follows: A person
         finding a nut with two kernels eats one, and gives the
         other to a person of the opposite sex, and then
         whichever says philopena first at the next meeting wins
         the present. The name is also applied to the kernels
         eaten.
         [1913 Webster] Philopolemic