"Octopus" (originally recorded as "Clowns and Jugglers" also known as "The Madcap Laughs", later remade as "Octopus") is a song by Syd Barrett. It appeared on his first solo album, The Madcap Laughs.

I carried that about in my head for about six months before I actually wrote it so maybe that's why it came out so well. The idea was like those number songs like Green Grow the Rushes, O where you have, say, twelve lines each related to the next and an overall theme. It's like a fool-proof combination of lyrics, really, and then the chorus comes in and changes the tempo but holds the whole thing together.

"Octopus" directly quotes a section from the poem "Rilloby-Rill" by Sir Henry Newbolt. The song features a variety of other influences as well.

After Barrett left Pink Floyd in April 1968, Peter Jenner from the band's management followed suit. Jenner led Barrett into EMI Studios to record some tracks in May, that would later be released on Barrett's first solo album. During the May sessions, Jenner failed to record, properly, any vocals at all, for several tracks one of them, "Clown and Jugglers". Sessions stopped once Barrett was in psychiatric care, apparently after a drive around Britain in his mini.

After New Year 1969, a somewhat recovered Barrett decided upon returning to a musical career; Barrett contacted EMI, and was passed on to Malcolm Jones, the then-head of EMI's new prog rock label, Harvest. Barrett wanted to recover the Jenner-produced sessions recordings; several tracks, including "Clowns and Jugglers", were improved upon.

An early version of the song was released on the Barrett rarities album Opel (1988) under the title "Clowns and Jugglers", which was recorded with the band Soft Machine. The 1993 re-releases of The Madcap Laughs and Opel contain alternate versions of "Octopus" and "Clowns and Jugglers" respectively, as bonus tracks.

The album's title came about as a result of co-producer David Gilmour mishearing a line from this song ("Well, the mad cat laughed at the man on the border..." - although the word "madcap" does figure in another of the song's lyrics, "To a madcap galloping chase"). "Octopus" is known for being Barrett's only single as a solo artist. It was released on 14 November 1969, two months before the release of The Madcap Laughs. In France, the single gained a picture sleeve, which had the drawing of an octopus on it.

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