Source : Webster's Revised Unabridged Dictionary (1913)

Outermost \Out"er*most`\, a. [See {Uttermost}, {Utmost}, and cf.
   {Outmost}.]
   Being on the extreme external part; farthest outward; as, the
   outermost row. --Boyle.

Source : WordNet®

outermost
     adj : situated at the farthest possible point from a center [syn:
           {outmost}]