Om

''Om'' emerged in the Vedic corpus and is said to be an encapsulated form of ''Samavedic'' chants or songs. It is a sacred spiritual incantation made before and during the recitation of spiritual texts, during ''puja'' and private prayers, in ceremonies of rites of passage (''samskara'') such as weddings, and during meditative and spiritual activities such as Pranava yoga. It is part of the iconography found in ancient and medieval era manuscripts, temples, monasteries, and spiritual retreats in Hinduism, Buddhism, Jainism, and Sikhism. As a syllable, it is often chanted either independently or before a spiritual recitation and during meditation in Hinduism, Buddhism, and Jainism.
The syllable ''Om'' is also referred to as Onkara (Omkara) and Pranava among many other names. Provided by Wikipedia
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