Denotes a keenness or willingness to participate, in reference to a suggestion. It is generally said with contextually embellished excitement, and emphasis on the rhyming factor of the phrase.

This phrase draws its origins from the Pierrot, or 'sad clown'.
by mbryo_ January 24, 2011
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To be ready or available for a proposed activity.
Q: do you want to go to that party?
A: I'm down like a clown in circus town!
by OberonCAS March 22, 2010
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