The Collaborative International Dictionary of English v.0.48:

Consound \Con"sound\ (-sound), n. [Corrupted fr. F. consoude, fr
   L. consolida comfrey (so called because supposed to have
   healing power); con- + solidus solid, consolidare to make
   solid. Cf. Comfrey, Consolidate.] (Bot.)
   A name applied loosely to several plants of different genera,
   esp. the comfrey.
   [1913 Webster]