unclasp \unclasp"\ u^nkl.asp", v. t. 1st pref. un- +
   clasp.
   to loose the clasp of; to open, as something that is fastened
   with, or as with, a clasp; as, to unclasp a book; to unclasp
   the hands; to unclasp one's heart.
   1913 webster

unclasp
     v : release from a clasp; "she clasped and unclasped her hands"
         ant: clasp, clasp
see also:
clasp 

36 moby thesaurus words for "unclasp":
   cast off, detach, disengage, doff, free, leave go, let go,
   let loose of, liberate, loose, loosen, release, remove, take off,
   unbar, unbind, unbolt, unbuckle, unbutton, unchain, unclutch, undo,
   unfasten, unfetter, unglue, unhand, unlace, unlatch, unleash,
   unlock, unloose, unloosen, unstick, unstrap, untie, weigh anchor