INHABITABLE is a 11 letter word that starts with I.

1. \In*hab"it*a*ble\, a. [L. inhabitabilis. See
   {Inhabit}.]
   Capable of being inhabited; habitable.
   
         Systems of inhabitable planets.          --Locke.
   
   

2. \In*hab"it*a*ble\, a. [L. inhabitabilis: cf. F.
   inhabitable. See {In-} not, and {Habitable}.]
   Not habitable; not suitable to be inhabited. [Obs.]
   
         The frozen ridges of the Alps Or other ground
         inhabitable.                             --Shak.