Sicker

Sick"er (?), v. i. [AS. sicerian.] (Mining) To percolate, trickle, or ooze, as water through a crack. [Also written sigger, zigger, and zifhyr.] [Prov. Eng.]

{ Sick"er, Sik"er }, adv. Surely; certainly. [Obs.]

Believe this as siker as your creed.
Chaucer.

Sicker, Willye, thou warnest well.
Spenser.

{ Sick"er, 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.