What is "eolipile"

AEolipile \[AE]*ol"i*pile\, AEolipyle \[AE]*ol"i*pyle\, n. [L. aeolipilae; Aeolus god of the winds + pila a ball, or Gr. ? gate (i. e., doorway of [AE]olus); cf. F. ['e]olipyle.] An apparatus consisting chiefly of a closed vessel (as a globe or cylinder) with one or more projecting bent tubes, through which steam is made to pass from the vessel, causing it to revolve. [Written also eolipile.]

Note: Such an apparatus was first described by Hero of Alexandria about 200 years b. c. It has often been called the first steam engine.

n. (alternative form of aeolipile English)