Source : Webster's Revised Unabridged Dictionary (1913)

Inmost \In"most`\, a. [OE. innemest, AS. innemest, a double
   superlative form fr. inne within, fr. in in. The modern form
   is due to confusion with most. See {In}, and cf. {Aftermost},
   {Foremost}, {Innermost}.]
   Deepest within; farthest from the surface or external part;
   innermost.

         And pierce the inmost center of the earth. --Shak.

         The silent, slow, consuming fires, Which on my inmost
         vitals prey.                             --Addison.

Source : WordNet®

inmost
     adj 1: being deepest within the self; "one's innermost feelings"
            [syn: {innermost}]
     2: situated or occurring farthest within; "the innermost
        chamber" [syn: {innermost}]