[1] : The Collaborative International Dictionary of English v.0.48

unfreeze \unfreeze"\, v. t. 1st pref. un- + freeze.
   to thaw. obs.
   1913 webster

[2] : WordNet (r) 2.0

unfreeze
     v 1: become or cause to become soft or liquid; "the sun melted
          the ice"; "the ice thawed"; "the ice cream melted"; "the
          heat melted the wax"; "the giant iceberg dissolved over
          the years during the global warming phase"; "dethaw the
          meat" syn: dissolve, thaw, unthaw, dethaw, melt
     2: make assets available; "release the holdings in the
        dictator's bank account" syn: unblock, free, release
        ant: freeze, freeze
     also: unfrozen, unfroze
see also:
dissolve thaw unthaw dethaw melt unblock 
free release freeze unfrozen unfroze 

Unfreeze >> U Words
Unfreeze, definition of term: Unfreeze
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