The Collaborative International Dictionary of English v.0.48:

Hag-taper \Hag"-ta`per\ (-t[=a]`p[~e]r), n. [Cf. 1st Hag, and
   Hig-taper.] (Bot.)
   The great woolly mullein (Verbascum Thapsus).
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Hig-taper \Hig"-ta`per\, n. [Cf. Hag-taper.] (Bot.)
   A plant of the genus Verbascum (Verbascum Thapsus); the
   common mullein. [Also high-taper and hag-taper.] Hijera