Source : Webster's Revised Unabridged Dictionary (1913)

Jenny \Jen"ny\, n.; pl. {Jennies}.
   1. A familiar or pet form of the proper name Jane.

   2. (Zo["o]l.) A familiar name of the European wren.

   {Jenny ass} (Zo["o]l.), a female ass.

Jenny \Jen"ny\, n. [A corruption of gin an engine; influenced by
   Jenny, the proper name. See {Gin} an engine, and cf.
   {Ginny-carriage}.]
   A machine for spinning a number of threads at once, -- used
   in factories.

Source : WordNet®

Jenny
     n 1: United States architect who designed the first skyscraper in
          which a metal skeleton was used (1832-1907) [syn: {William
          Le Baron Jenny}]
     2: female donkey [syn: {jennet}, {jenny ass}]