The Collaborative International Dictionary of English v.0.48:

Demit \De*mit"\, v. t. [imp. & p. p. Demitted; p. pr. & vb. n.
   Demitting.] [L. demittere to send or bring down, to lower;
   de- + mittere to send. Cf. Demise.]
   1. To let fall; to depress. [R.]
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            They [peacocks] demit and let fall the same [i. e.,
            their train].                         --Sir T.
                                                  Browne.
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   2. To yield or submit; to humble; to lower; as, to demit
      one's self to humble duties. [R.]
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   3. To lay down, as an office; to resign. [Scot.]
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            General Conway demitted his office.   --Hume.
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