aaron's rod Meaning, Definition & Usage

  1. noun tall-stalked very woolly mullein with densely packed yellow flowers; ancient Greeks and Romans dipped the stalks in tallow for funeral torches
    common mullein; woolly mullein; great mullein; torch; flannel mullein; Verbascum thapsus.

WordNet

Aar"on's rod`
Etymology
See Exodus vii. 9 and Numbers xvii. 8
Definitions
  1. (Arch.) A rod with one serpent twined around it, thus differing from the caduceus of Mercury, which has two.
  2. (Bot.) A plant with a tall flowering stem; esp. the great mullein, or hag-taper, and the golden-rod.

Webster 1913