Source : Webster's Revised Unabridged Dictionary (1913)

Subjacent \Sub*ja"cent\, a. [L. subjacens, p. pr. of subjacere
   to lie under; sub under + jacere to lie.]
   1. Lying under or below.

   2. Being in a lower situation, though not directly beneath;
      as, hills and subjacent valleys.

Source : WordNet®

subjacent
     adj : lying nearby but lower; "hills and subjacent valleys" [ant:
           {superjacent}]