What is the origin of the word "Keccak"? Where does the word or acronym Keccak come from?


Guido Bertoni, Joan Daemen, Michael Peeters, and Gilles Van Assche. Keccak sponge function family main document. Submission to NIST (updated), 2009.
"NIST Selects Winner of Secure Hash Algorithm (SHA-3) Competition". NIST 10/2/2012.
According to J.-P. Aumasson (who's one of the authors of another SHA-3 finalist, BLAKE, and who participated in the cryptanalysis of Keccak), the name "Keccak" is a variant spelling of "Kecak", a type of Balinese dance.

So far, that's the most authoritative reference I've been able to come up with.  It should be noted that naming crypto primitives after dances is hardly a new thing; see e.g. D. J. Bernstein's "latin dances" (Salsa, Rumba and ChaCha).