The family of all sponge functions with a KECCAK-f permutation as the underlyinng function and multi-rate padding as the padding rule. KECCAK was originally specified in [G. Bertoni, J. Daemen, M. Peeters, and G. Van Assche, The KECCAK reference, version 3.0], and standardized in FIPS 202.
Sources:
NIST SP 800-185