The Collaborative International Dictionary of English v.0.48:

Areng \A*reng"\, Arenga \A*ren"ga\, n. [Malayan.]
   A palm tree (Saguerus saccharifer) which furnishes sago,
   wine, and fibers for ropes; the gomuti palm.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Arenga
    n 1: a genus of tropical Asian and Malaysian palm trees [syn:
         Arenga, genus Arenga]