Sickerly

from The Collaborative International Dictionary of English v.0.48

Sickerly \Sick"er*ly\, Sikerly \Sik"er*ly\, adv.
   Surely; securely. [Obs.]
   [1913 Webster]

         But sikerly, withouten any fable.        --Chaucer.
   [1913 Webster] Sickerness