Om /(?)/

Om

interj. & n.
  1. A mystic syllable or ejaculation used by Hindus and Buddhists in religious rites, -- orig. among the Hindus an exclamation of assent, like Amen, then an invocation, and later a symbol of the trinity formed by Vishnu, Siva, and Brahma.

Phrases & Compounds
Om mani padme hun
a sacred formula of buddhism (esp. of the Lamaists) translated “O, the Jewel in the Lotus, Amen,” and referring to Amitabha, who is commonly represented as standing or sitting within a lotus.