I always enjoy encountering a word that I’ve never read or heard before.
Lexico.com provides this meaning:
Whispering or rustling.
‘the susurration of the river’
‘It settled to the ground with a soft susurration like stirring leaves.’
‘Something beautiful but so far away-like the music of a faraway violin or the susurration of a distant wave.’
Late Middle English from late Latin susurratio(n-), from Latin susurrare ‘to murmur, hum’, from susurrus ‘whisper’.