The Collaborative International Dictionary of English v.0.48:

Anan \A*nan"\, interj. [See Anon.]
   An expression equivalent to What did you say? Sir? Eh? [Obs.]
   --Shak.
   [1913 Webster]

Easton's 1897 Bible Dictionary:

Anan
   cloud, one of the Israelites who sealed the covenant after the
   return from Babylon (Neh. 10:26).