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

aaron's rod \aar"on's rod`\ ^ar"u^nz ro^d`. see exodus
   vii. 9 and numbers xvii. 8
   1. arch. a rod with one serpent twined around it, thus
      differing from the caduceus of mercury, which has two.
      1913 webster

   2. bot. a plant with a tall flowering stem; esp. the great
      mullein, or hag-taper, and the golden-rod.
      1913 webster

[2] : WordNet (r) 2.0

aaron's rod
     n : tall-stalked very woolly mullein with densely packed yellow
         flowers; ancient greeks and romans dipped the stalks in
         tallow for funeral torches syn: common mullein, great
         mullein, flannel mullein, woolly mullein, torch, verbascum
         thapsus
see also:
common mullein great mullein flannel mullein woolly mullein torch verbascum thapsus 

Aarons Rod >> A Words
Aarons Rod, definition of term: Aarons Rod
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