murmuration
mur-mur-AY-shun
The collective behavior of starlings flying in dense, shape-shifting flocks at dusk — thousands of birds moving as a single, fluid organism, expanding and contracting in patterns that no individual bird directs. Also the word for a flock of starlings. The sound is part of the name — the low, continuous hum of ten thousand pairs of wings beating in near-unison.
Etymology
From Latin murmuratio, a murmuring, a low continuous sound. The word was first recorded as a collective noun for starlings in the 15th-century Book of St. Albans, a handbook for English nobility.
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