Definition of Pranava

"Of all the syllables, the most powerful and the most significant one is the single syllable called the Pranava, the 'AUM', or Omkara, pronounced as 'Om'. Omkara is the holiest Vedic sound in the Hindu tradition, explaining various religious and spiritual ideas. The syllable has sound, meaning, application and efficiency. It is the apt symbol of the Supreme. The formless lord Siva assumes the form to dance and becomes Lord Nataraja. Lord Nataraja holds in his upper right hand a small drum (damaru), which is shaped like the hour-glass, denoting the connection between sound and eternal time. He beats the drum when the primordial sound, Pranava (Om), is produced. This sound fills the universe and modifies the matter and space. The evolution of the subtle as well as the gross universe, with all its entities, takes place. Further, all that is past, present and future and any thing beyond them is, verily, the manifestation of Pranava as Time, as stated in Mandukya Upanishad … To every mantra, Om, the Pranava, is added. And without Om, no sacred chant has its power. By the addition of the Pranava to any mantra, a life-giving breath flows through it. "