"Om" is a 1968 song by the British progressive rock band The Moody Blues. It was composed by the band's keyboardist Mike Pinder. "Om" has a heavy Indian influence and sound to it. "Om," which is chanted repeatedly throughout the song, represents Aum, a sacred mantra in the Hindu, Jain Sikh and Buddhist religions.

"Om" is the final track on the Moody Blues 1968 album In Search of the Lost Chord. On the album, "Om" is preceded by a short spoken-word interlude named "The Word". "The Word" was written by drummer Graeme Edge, and is recited by Mike Pinder. "The Word" explains the album's concept, and that the mantra "Om" is the lost chord referenced in the album's title, which concludes with:

To name the chord is important to some.
So they give it a word,
And the word is "Om"

While "The Word" and "Om" are generally played together, "The Word" was released on The Moody Blues 1974 compilation This Is The Moody Blues without "Om." However, the final word of "The Word", which is also the first word of "Om", was included.

Like many of the album's preceding tracks, "Om" make use of a variety of different instruments. "Om" features both Mike Pinder and Ray Thomas on lead vocals, and on their usual instruments, the mellotron and the flute, respectively. The remaining band members are featured on instrument other than their usual instruments, which includes Justin Hayward on sitar, John Lodge on cello, and Graeme Edge on tabla, a popular Indian percussion instrument used in the classical, popular and devotional music of the Indian subcontinent and in Hindustani classical music.

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