Source : Webster's Revised Unabridged Dictionary (1913)

Snore \Snore\ (sn[=o]r), v. i. [imp. & p. p. {Snored}
   (sn[=o]rd); p. pr. & vb. n. {Snoring}.] [OE. snoren, AS.
   snora a snoring; akin to LG. snoren, snorken, snurken, to
   snore, D. snorken, G. schnarchen to snore, schnarren to
   rattle, MHG. snarren, Sw. snarka to snore, Icel. snarka to
   sputter, fizzle. Cf. {Snarl} to growl, {Sneer}, {Snort}. See
   {Snoring}.]
   To breathe with a rough, hoarse, nasal voice in sleep.

Snoring \Snor"ing\, n. (Physiol.)
   The act of respiring through the open mouth so that the
   currents of inspired and expired air cause a vibration of the
   uvula and soft palate, thus giving rise to a sound more or
   less harsh. It is usually unvoluntary, but may be produced
   voluntarily.

Source : WordNet®

snoring
     adj : breathing during sleep with harsh noises caused by vibration
           of the uvula or soft palate; "the snoring sleeper"
     n : the act of snoring or producing a snoring sound [syn: {snore},
          {stertor}]