The Collaborative International Dictionary of English v.0.48:

Dissemble \Dis*sem"ble\, v. t. [imp. & p. p. Dissembled; p.
   pr. & vb. n. Dissembling.] [OF. dissembler to be
   dissimilar; pref. dis- (L. dis-) + F. sembler to seem, L.
   simulare to simulate; cf. L. dissimulare to dissemble. See
   Simulate, and cf. Dissimulate.]
   1. To hide under a false semblance or seeming; to feign
      (something) not to be what it really is; to put an untrue
      appearance upon; to disguise; to mask.
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            Dissemble all your griefs and discontents. --Shak.
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            Perhaps it was right to dissemble your love,
            But -- why did you kick me down stairs? --J. P.
                                                  Kemble.
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   2. To put on the semblance of; to make pretense of; to
      simulate; to feign.
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            He soon dissembled a sleep.           --Tatler.

   Syn: To conceal; disguise; cloak; cover; equivocate. See
        Conceal.
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