Siker \Sik"er\, a. & adv., Sikerly \Sik"er*ly\, adv., Sikerness \Sik"er*ness\, n., etc. See 2d {Sicker}, {Sickerly}, etc. [Obs.]
Sicker \Sick"er\, Siker \Sik"er\, a. [OE. siker; cf. OS. sikur, LG. seker, D. zeker, Dan. sikker, OHG. sihhur, G. sicher; all fr. L. securus. See {Secure}, {Sure}.] Sure; certain; trusty. [Obs. or Prov. Eng. & Scot.] --Burns.
When he is siker of his good name. --Chaucer.
Sicker \Sick"er\, Siker \Sik"er\, adv. Surely; certainly. [Obs.]