bourdon

/ˈbʊrdən/
noun
  1. A low-pitched stop on a pipe organ or a similar deep, sustained sound.
    • The organist pulled out the bourdon stop to add a deep bass to the hymn.
    • The bourdon of the organ filled the cathedral with a rumbling sound.
    • He practiced playing the bourdon notes to strengthen his left hand.
  2. A low, humming or droning sound, like that of a bee or a distant engine.
    • From the hill, we could hear the bourdon of traffic on the highway.
    • The bourdon of the bees in the garden was a peaceful background noise.
    • The bourdon of the old refrigerator kept her awake at night.
Synonyms
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