Webster’s Revised Unabridged Dictionary · 1913
Jenny
Jen′ny (·ny̆), n.; pl. Jennies.
1. A familiar or pet form of the proper name Jane.
2. (Zoöl.) A familiar name of the European wren.
Jenny ass (Zoöl.), a female ass.
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.