The Collaborative International Dictionary of English v.0.48:

Consternation \Con`ster*na"tion\, n. [L. consternatio, fr.
   consternare to overome, perplex, an accessory form of
   consternere to throw down, prostrate; con + sternere to
   spread out, throw down: cf. F. consternation. See Stratum.]
   Amazement or horror that confounds the faculties, and
   incapacitates for reflection; terror, combined with
   amazement; dismay.
   [1913 Webster]

         The chiefs around,
         In silence wrapped, in consternation drowned.
         Attend the stern reply.                  --Pope.

   Syn: Alarm; fright; amazement; astonishment; surprise; panic;
        perturbation. See Alarm.
        [1913 Webster]

WordNet (r) 3.0 (2006):

consternation
    n 1: fear resulting from the awareness of danger [syn: alarm,
         dismay, consternation]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "consternation":
   abject fear, affright, alarm, awe, bewilderment, blue funk,
   confusion, cowardice, dismay, distraction, dread, fear, fright,
   funk, horrification, horror, muddle, muddlement, panic, panic fear,
   perplexity, phobia, scare, stampede, terror, trepidation,
   trepidity, unholy dread