Source : Webster's Revised Unabridged Dictionary (1913)

Reverential \Rev`er*en"tial\, a. [Cf. F. r['e]v['e]renciel. See
   {Reverence}.]
   Proceeding from, or expressing, reverence; having a reverent
   quality; reverent; as, reverential fear or awe. ``A
   reverential esteem of things sacred.'' --South.

Source : WordNet®

reverential
     adj : feeling or manifesting veneration [syn: {respectful}, {venerating}]