The Collaborative International Dictionary of English v.0.48:

Deter \De*ter"\, v. t. [imp. & p. p. Deterred; p. pr. & vb. n.
   Deterring.] [L. deterrere; de + terrere to frighten,
   terrify. See Terror.]
   To prevent by fear; hence, to hinder or prevent from action
   by fear of consequences, or difficulty, risk, etc. --Addison.
   [1913 Webster]

         Potent enemies tempt and deter us from our duty.
                                                  --Tillotson.
   [1913 Webster]

         My own face deters me from my glass.     --Prior.
   [1913 Webster]

WordNet (r) 3.0 (2006):

deter
    v 1: try to prevent; show opposition to; "We should discourage
         this practice among our youth" [syn: deter, discourage]
    2: turn away from by persuasion; "Negative campaigning will only
       dissuade people" [syn: dissuade, deter] [ant: persuade]

Moby Thesaurus II by Grady Ward, 1.0:

64 Moby Thesaurus words for "deter":
   anticipate, avert, awe, bar, block, blunt, check, chill, cool,
   damp, dampen, daunt, debar, deflect, disaffect, discourage,
   dishearten, disincline, disinterest, dissuade, distract, divert,
   estop, exclude, faze, fend, fend off, forbid, foreclose, forestall,
   frighten, help, hinder, impede, indispose, inhibit, intimidate,
   keep from, keep off, obstruct, obviate, overawe, preclude, prevent,
   prohibit, put off, quench, repel, restrain, rule out, save, scare,
   scare off, shake, shut out, stave off, stop, turn aside, turn away,
   turn from, turn off, ward, ward off, wean from