Word

OM

Sanskrit

ॐ

IAST

oṃ

In General

OM or AUM is called the Pranava or the sacred syllable symbolizing and embodying Brahman. It is a sound symbol. OM is prefixed to many mantras to get more reverence to the Mantras

The three roots of the syllable OM are A + U + M. Mandukya Upanishad adds silence (A + U + M + "silence") to this list and thus OM start from silence and ends with silence. The triads A + U + M stands for Bhuh-Buvah-Svar so also for Brahma-Vishnu-Siva, creation-existence-Annihilation, Past-Present-Future, Vayu-Agni-Aditya, Rik-Saman-Yajur

OM is a revered mantra to every Hindu text, Bhagavad Gita (9.17) says: I am the Father of this world, Mother, Ordainer, Grandfather, the Thing to be known, the Purifier, the syllable Om, Rik, Saman and also Yajus. BG (17.23) says OM Tat Sat, OM It is the reality.

Veda

OM is the essence of Veda. The direct representation of OM is not found in RigVeda. Creative power of existence is termed as Vak in RigVeda ; this is similar to what we mean by OM. We find the single syllable OM first in YajurVeda

The Aitareya Brahmana of Rig Veda, in section 5.32, states that, OM is the creative powers of the universe.

OM is explained in various ways Upanishads . To most of them it is a mantra for meditation of the Ultimate Reality