su·sur·ra·tion (sū'sə-rā'shən) also su·sur·rus (sʊ-sûr'əs, -sŭr'-)
n.
A soft, whispering or rustling sound; a murmur.

[Middle English susurracioun, from Late Latin susurrātiō, susurrātiōn-, from Latin susurrātus, past participle of susurrāre, to whisper, from susurrus, whisper, ultimately of imitative origin.]