Source : Webster's Revised Unabridged Dictionary (1913)

Smirk \Smirk\, v. i. [imp. & p. p. {Smirked}; p. pr. & vb. n.
   {Smirking}.] [OE. smirken, ASS. smercian, smearcian; cf. MHG.
   smieren, smielen, to smile. See {Smile}, v. i.]
   To smile in an affected or conceited manner; to smile with
   affected complaisance; to simper.