Snoring is defined as a coarse sound made by vibrations of the soft palate and other tissue in the mouth, nose & throat (upper airway). It is caused by turbulence inside the airway during inspiration. The turbulence is caused by a partial blockage that may be located anywhere from the tip of the nose to the vocal chords. Snoring may be a symptom of a sleep-disordered breathing that requires medical attention.
This condition, sometimes referred to as sleep apnea, involves repeated arousals from sleep--not necessarily to full awakening because breathing has ceased. In the most important form (obstructive sleep apnea) it is because the upper airway for breathing has momentarily been obstructed.