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Main Entry: su·sur·rus
Pronunciation: su-'s&r-&s, -'s&-r&s
Function: noun
Etymology: Latin, hum, whisper -- more at SWARM
: a whispering or rustling sound
- su·sur·rant /-'s&r-&nt, -'s&-r&nt/ adjective
A sussurant stir went thru' the crowd at Stan's revelation of true murderer.

We can hear this every summer night in the trees..... insects that whisper their secrets from the day all at once and over and over.

Katy,

I love this word but its synonym has a fourth S, so I'm going with it. I don't think a word could get any more onomatopoetic.

Portuguese/Italian: sussurro
Spanish: susurro
Romanian: susur

Apparently French has only the verb susurrer, but no noun, and I didn't find anything for Catalan, which is odd.

Brazilian dude