The Collaborative International Dictionary of English v.0.48:

Dander \Dan"der\, n. [Corrupted from dandruff.]
   1. Dandruff or scurf on the head.
      [1913 Webster]

   2. Anger or vexation; rage. [Low] --Halliwell.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dander \Dan"der\, v. i. [See Dandle.]
   To wander about; to saunter; to talk incoherently. [Prov.
   Eng.] --Halliwell.
   [1913 Webster]

WordNet (r) 3.0 (2006):

dander
    n 1: small scales from animal skins or hair or bird feathers
         that can cause allergic reactions in some people
    2: a feeling of anger and animosity; "having one's hackles or
       dander up" [syn: dander, hackles]