The Collaborative International Dictionary of English v.0.48:

Ironical \I*ron"ic*al\, a. [LL. ironicus, Gr. ? dissembling: cf.
   F. ironique. See Irony.]
   [1913 Webster]
   1. Pertaining to irony; containing, expressing, or
      characterized by, irony; as, an ironical remark.
      [1913 Webster]

   2. Addicted to the use of irony; given to irony. --
      I*ron"ic*al*ly, adv. -- I*ron"ic*al*ness, n.
      [1913 Webster]