AUTOGENOUS is a 10 letter word that starts with A.

1. \Au*tog"e*nous\, a. [Gr. ?; ? self + root of ? to be
   born.]
   1. (Biol.) Self-generated; produced independently.
   
   2. (Anat.) Developed from an independent center of
      ossification. --Owen.
   
   {Autogenous soldering}, the junction by fusion of the joining
      edges of metals without the intervention of solder.
   
   

2. \Au*tog"e*nous\, a.
   Autogenetic.