athenaeum noun. 
[aƟɪ'ni:ǝm] Also *
atheneum. 
M18.[Latin Athenaeum from Greek Athēnaion.]1.  (
Athenaeum.) The temple of the goddess Athene in ancient Athens, which was used for teaching. 
M18.2.  A reading-room, a library. 
L18.b. A literary or scientific club. 
E19.3.  (
Athenaeum.) As the title of various periodicals devoted to literature, science, and art. 
M19.  [TahlilGaran] English Dictionary ▲