The Collaborative International Dictionary of English v.0.48:

Uncase \Un*case"\, v. t. [1st pref. un- + case.]
   [1913 Webster]
   1. To take out of a case or covering; to remove a case or
      covering from; to uncover. --L'Estrange.
      [1913 Webster]

   2. To strip; to flay. [Obs.]
      [1913 Webster]

   3. (Mil.) To display, or spread to view, as a flag, or the
      colors of a military body.
      [1913 Webster]

WordNet (r) 3.0 (2006):

uncase
    v 1: get undressed; "please don't undress in front of
         everybody!"; "She strips in front of strangers every night
         for a living" [syn: undress, discase, uncase,
         unclothe, strip, strip down, disrobe, peel] [ant:
         apparel, clothe, dress, enclothe, fit out,
         garb, garment, get dressed, habilitate, raiment,
         tog]