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

unbrace \unbrace"\, v. t. 1st pref. un- + brace.
   to free from tension; to relax; to loose; as, to unbrace a
   drum; to unbrace the nerves. --spenser.
   1913 webster

[2] : WordNet (r) 2.0

unbrace
     v 1: undo the ties of; "they untied the prisoner" syn: untie,
          unlace ant: tie
     2: remove from tension
     3: remove a brace or braces from
     4: remove a brace or braces form
see also:
untie unlace tie 

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