Māndūkya Upanishad is one of the shortest
Upanishads that form the revealed, so called metaphysical, parts of the
Vedas. It belongs to the
Atharva Veda. It devotes itself entirely to the explanation of the spiritual - mystic - syllable
Aum. It is in prose, consisting of twelve sentences.
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Mandukya Upanishad or Mandukyopanisad (Sanskrit) [from manduka frog] A short but important Upanishad of the Atharva-Veda.