Source : Webster's Revised Unabridged Dictionary (1913)

Smegma \Smeg"ma\, n. [NL., fr. Gr. ???? soap, fr. ????? to wash
   off.] (Physiol.)
   The matter secreted by any of the sebaceous glands.
   Specifically:
   (a) The soapy substance covering the skin of newborn infants.
   (b) The cheesy, sebaceous matter which collects between the
       glans penis and the foreskin.

Source : WordNet®

smegma
     n : a white secretion of the sebaceous glands of the foreskin